diff --git a/CMakeLists.txt b/CMakeLists.txt
index b4bfe5981e5c3f524c6d781665c100e33b0713ca..bf1d35bc51e16cc2975edd905a2c938a4eb1af83 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -61,6 +61,7 @@ lite_option(LITE_WITH_ARM  "Enable ARM in lite mode"  OFF)
 lite_option(LITE_WITH_NPU  "Enable NPU in lite mode"  OFF)
 lite_option(LITE_WITH_XPU  "Enable XPU in lite mode"  OFF)
 lite_option(LITE_WITH_BM   "Enable BM in lite mode"   OFF)
+lite_option(LITE_WITH_TRAIN "Enable training operators and kernels in lite" OFF)
 lite_option(LITE_WITH_OPENMP "Enable OpenMP in lite framework" ON)
 lite_option(LITE_WITH_OPENCL   "Enable OpenCL support in lite" OFF)
 lite_option(LITE_WITH_FPGA   "Enable FPGA support in lite" OFF)
diff --git a/cmake/configure.cmake b/cmake/configure.cmake
index 752b22461d9d1c36b3ca6a0bfe472a5dcc3ab976..d38c78f62fa2bed4f4483355de0683f1f5b7656b 100644
--- a/cmake/configure.cmake
+++ b/cmake/configure.cmake
@@ -122,6 +122,9 @@ if (LITE_WITH_ARM)
     endif()
 endif()
 
+if (LITE_WITH_TRAIN)
+    add_definitions("-DLITE_WITH_TRAIN")
+endif()
 
 if (WITH_ARM_DOTPROD)
     add_definitions("-DWITH_ARM_DOTPROD")
diff --git a/lite/api/cxx_api.cc b/lite/api/cxx_api.cc
index f6f7ec75e65ff54e3f3642822e51057d3522ae3a..b739c78f7c883d62b39d88ae1a7f4bf76ae8932c 100644
--- a/lite/api/cxx_api.cc
+++ b/lite/api/cxx_api.cc
@@ -333,16 +333,16 @@ lite::Tensor *Predictor::GetInputByName(const std::string &name) {
   }
 }
 
-#ifdef LITE_WITH_TRAIN
-void Predictor::FeedVars(const std::vector<framework::Tensor> &tensors) {
-  auto var = scope_->FindVar("feed");
-  auto &feed_list = *(var->GetMutable<std::vector<lite::Tensor>>());
-  feed_list.resize(tensors.size());
-
-  for (size_t i = 0; i < tensors.size(); ++i)
-    feed_list[i].ShareDataWith(tensors[i]);
-}
-#endif
+// #ifdef LITE_WITH_TRAIN
+// void Predictor::FeedVars(const std::vector<framework::Tensor> &tensors) {
+//   auto var = scope_->FindVar("feed");
+//   auto &feed_list = *(var->GetMutable<std::vector<lite::Tensor>>());
+//   feed_list.resize(tensors.size());
+
+//   for (size_t i = 0; i < tensors.size(); ++i)
+//     feed_list[i].ShareDataWith(tensors[i]);
+// }
+// #endif
 
 }  // namespace lite
 }  // namespace paddle
diff --git a/lite/api/cxx_api.h b/lite/api/cxx_api.h
index 504710d9fa29420b8762f31e0c675b59c6c626bd..e63893cb91e112beb6be50bd661a57b9738e5fb1 100644
--- a/lite/api/cxx_api.h
+++ b/lite/api/cxx_api.h
@@ -101,14 +101,14 @@ class LITE_API Predictor {
       bool record_info = false);
   void SaveOpKernelInfo(const std::string& model_dir);
 
-#ifdef LITE_WITH_TRAIN
-  void Run(const std::vector<framework::Tensor>& tensors) {
-    FeedVars(tensors);
-    program_->Run();
-  }
-
-  void FeedVars(const std::vector<framework::Tensor>& tensors);
-#endif
+  // #ifdef LITE_WITH_TRAIN
+  //   void Run(const std::vector<framework::Tensor>& tensors) {
+  //     FeedVars(tensors);
+  //     program_->Run();
+  //   }
+
+  //   void FeedVars(const std::vector<framework::Tensor>& tensors);
+  // #endif
 
  private:
   Optimizer optimizer_;
diff --git a/lite/kernels/arm/CMakeLists.txt b/lite/kernels/arm/CMakeLists.txt
index 49078844354c8597ea489a986826edbdbcc9eb62..26ae22ce9d27cffcb6adf53ca16b01181edddf9e 100644
--- a/lite/kernels/arm/CMakeLists.txt
+++ b/lite/kernels/arm/CMakeLists.txt
@@ -105,6 +105,11 @@ add_kernel(lod_reset_compute_arm ARM extra SRCS lod_reset_compute.cc DEPS ${lite
 add_kernel(is_empty_compute_arm ARM extra SRCS is_empty_compute.cc DEPS ${lite_kernel_deps} math_arm)
 add_kernel(lstm_arm ARM extra SRCS lstm_compute.cc DEPS ${lite_kernel_deps} math_arm)
 
+# 4. training kernels
+add_kernel(mean_compute_arm ARM extra SRCS mean_compute.cc DEPS ${lite_kernel_deps} math_arm)
+if(LITE_WITH_TRAIN)
+  add_kernel(mean_grad_compute_arm ARM extra SRCS mean_grad_compute.cc DEPS ${lite_kernel_deps} math_arm)
+endif()
 
 lite_cc_test(test_scale_compute_arm SRCS scale_compute_test.cc DEPS scale_compute_arm)
 lite_cc_test(test_softmax_compute_arm SRCS softmax_compute_test.cc DEPS softmax_compute_arm)
diff --git a/lite/kernels/arm/mean_compute.cc b/lite/kernels/arm/mean_compute.cc
new file mode 100644
index 0000000000000000000000000000000000000000..5d1a5b8508c4cd7bd36bf7809c445e57bbef428e
--- /dev/null
+++ b/lite/kernels/arm/mean_compute.cc
@@ -0,0 +1,47 @@
+// Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "lite/kernels/arm/mean_compute.h"
+
+namespace paddle {
+namespace lite {
+namespace kernels {
+namespace arm {
+
+void MeanCompute::Run() {
+  auto& param = this->Param<operators::MeanParam>();
+  const auto* input = param.X;
+  auto* output = param.Out;
+  auto x_dim = input->dims();
+  auto x_data = input->data<float>();
+  auto out_data = output->mutable_data<float>();
+
+  int x_size = x_dim.production();
+  float sum = 0;
+  for (int i = 0; i < x_size; i++) {
+    sum += x_data[i];
+  }
+  out_data[0] = sum / x_size;
+}
+
+}  // namespace arm
+}  // namespace kernels
+}  // namespace lite
+}  // namespace paddle
+
+REGISTER_LITE_KERNEL(
+    mean, kARM, kFloat, kNCHW, paddle::lite::kernels::arm::MeanCompute, def)
+    .BindInput("X", {LiteType::GetTensorTy(TARGET(kARM))})
+    .BindOutput("Out", {LiteType::GetTensorTy(TARGET(kARM))})
+    .Finalize();
diff --git a/lite/kernels/arm/mean_compute.h b/lite/kernels/arm/mean_compute.h
new file mode 100644
index 0000000000000000000000000000000000000000..ba4650c6c84e270ba9b174cc09fba4bd63b486f5
--- /dev/null
+++ b/lite/kernels/arm/mean_compute.h
@@ -0,0 +1,36 @@
+// Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#pragma once
+#include "lite/core/kernel.h"
+#include "lite/operators/mean_op.h"
+
+namespace paddle {
+namespace lite {
+namespace kernels {
+namespace arm {
+
+class MeanCompute : public KernelLite<TARGET(kARM), PRECISION(kFloat)> {
+ public:
+  using param_t = operators::MeanParam;
+
+  void Run() override;
+
+  virtual ~MeanCompute() = default;
+};
+
+}  // namespace arm
+}  // namespace kernels
+}  // namespace lite
+}  // namespace paddle
diff --git a/lite/kernels/arm/mean_grad_compute.cc b/lite/kernels/arm/mean_grad_compute.cc
new file mode 100644
index 0000000000000000000000000000000000000000..f7a5be8be1ebd4e02a188ab40026de04b319c76e
--- /dev/null
+++ b/lite/kernels/arm/mean_grad_compute.cc
@@ -0,0 +1,54 @@
+// Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "lite/kernels/arm/mean_grad_compute.h"
+
+namespace paddle {
+namespace lite {
+namespace kernels {
+namespace arm {
+
+void MeanGradCompute::Run() {
+  auto& param = this->Param<operators::MeanGradParam>();
+  const auto* input = param.X;
+  const auto* out_grad = param.Out_grad;
+  auto* input_grad = param.X_grad;
+
+  auto out_grad_data = out_grad->data<float>();
+  auto input_data = input->data<float>();
+  auto input_grad_data = input_grad->mutable_data<float>();
+
+  int input_grad_size = input_grad->dims().production();
+
+  // TODO(mapingshuo): use parallel methods to accelerate this for loop
+  for (int i = 0; i < input_grad_size; i++) {
+    input_grad_data[i] = out_grad_data[0] / input_grad_size;
+  }
+}
+
+}  // namespace arm
+}  // namespace kernels
+}  // namespace lite
+}  // namespace paddle
+
+REGISTER_LITE_KERNEL(mean_grad,
+                     kARM,
+                     kFloat,
+                     kNCHW,
+                     paddle::lite::kernels::arm::MeanGradCompute,
+                     def)
+    .BindInput("X", {LiteType::GetTensorTy(TARGET(kARM))})
+    .BindInput("Out@GRAD", {LiteType::GetTensorTy(TARGET(kARM))})
+    .BindOutput("X@GRAD", {LiteType::GetTensorTy(TARGET(kARM))})
+    .Finalize();
diff --git a/lite/kernels/arm/mean_grad_compute.h b/lite/kernels/arm/mean_grad_compute.h
new file mode 100644
index 0000000000000000000000000000000000000000..49a72e9520df95082ba0a518b664b21613baf153
--- /dev/null
+++ b/lite/kernels/arm/mean_grad_compute.h
@@ -0,0 +1,36 @@
+// Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#pragma once
+#include "lite/core/kernel.h"
+#include "lite/operators/mean_grad_op.h"
+
+namespace paddle {
+namespace lite {
+namespace kernels {
+namespace arm {
+
+class MeanGradCompute : public KernelLite<TARGET(kARM), PRECISION(kFloat)> {
+ public:
+  using param_t = operators::MeanGradParam;
+
+  void Run() override;
+
+  virtual ~MeanGradCompute() = default;
+};
+
+}  // namespace arm
+}  // namespace kernels
+}  // namespace lite
+}  // namespace paddle
diff --git a/lite/operators/CMakeLists.txt b/lite/operators/CMakeLists.txt
index 512473c7d52d0f43b01611048012a8c54e2b7244..36d69e68b5c43b2da3fd3794186cb8c46a78dabc 100644
--- a/lite/operators/CMakeLists.txt
+++ b/lite/operators/CMakeLists.txt
@@ -18,7 +18,6 @@ add_operator(activation_ops basic SRCS activation_ops.cc DEPS ${op_DEPS})
 add_operator(elementwise_ops basic SRCS elementwise_ops.cc DEPS ${op_DEPS})
 add_operator(box_coder_op_lite basic SRCS box_coder_op.cc DEPS ${op_DEPS})
 add_operator(multiclass_nms_op_lite basic SRCS multiclass_nms_op.cc DEPS ${op_DEPS})
-add_operator(mean_op basic SRCS mean_op.cc DEPS ${op_DEPS})
 add_operator(fill_constant_op basic SRCS fill_constant_op.cc DEPS ${op_DEPS})
 add_operator(fill_constant_batch_size_like_op basic SRCS fill_constant_batch_size_like_op.cc DEPS ${op_DEPS})
 add_operator(shuffle_channel_op basic SRCS shuffle_channel_op.cc DEPS ${op_DEPS})
@@ -139,6 +138,12 @@ add_operator(sequence_topk_avg_pooling_op basic SRCS sequence_topk_avg_pooling_o
 add_operator(search_fc_op basic SRCS search_fc_op.cc DEPS ${op_DEPS})
 add_operator(lstm_op extra SRCS lstm_op.cc DEPS ${op_DEPS})
 
+# 4. training op
+add_operator(mean_op extra SRCS mean_op.cc DEPS ${op_DEPS})
+if (LITE_WITH_TRAIN)
+  add_operator(mean_grad_op extra SRCS mean_grad_op.cc DEPS ${op_DEPS})
+endif()
+
 if (NOT LITE_WITH_X86)
     lite_cc_test(test_fc_op SRCS fc_op_test.cc
                 DEPS fc_op memory
diff --git a/lite/operators/activation_ops.cc b/lite/operators/activation_ops.cc
index 4ccb1be2a96a06ec56adacde64b963c9038871d1..0e31d758b728dc9d87b07b3f0833e0512b38a19d 100644
--- a/lite/operators/activation_ops.cc
+++ b/lite/operators/activation_ops.cc
@@ -78,45 +78,45 @@ bool ActivationOp::AttachImpl(const cpp::OpDesc& opdesc, lite::Scope* scope) {
   return true;
 }
 
-#ifdef LITE_WITH_TRAIN
-
-bool ActivationGradOp::CheckShape() const {
-  CHECK_OR_FALSE(param_.X_grad);
-  CHECK_OR_FALSE(param_.Out_grad);
-  return true;
-}
-
-bool ActivationGradOp::InferShape() const {
-  param_.X_grad->Resize(param_.Out_grad->dims());
-  return true;
-}
-
-bool ActivationGradOp::AttachImpl(const cpp::OpDesc& opdesc,
-                                  lite::Scope* scope) {
-  auto Out_grad_name = opdesc.Input(framework::GradVarName("Out")).front();
-  auto X_grad_name = opdesc.Output(framework::GradVarName("X")).front();
-
-  param_.Out_grad = GetVar<lite::Tensor>(scope, Out_grad_name);
-  param_.X_grad = GetMutableVar<Tensor>(scope, X_grad_name);
-
-  if (opdesc.HasInput("X")) {
-    auto X_name = opdesc.Input("X").front();
-    param_.X = GetVar<lite::Tensor>(scope, X_name);
-  } else {
-    param_.X = param_.X_grad;
-  }
-
-  if (opdesc.HasInput("Out")) {
-    auto Out_name = opdesc.Input("Out").front();
-    param_.Out = GetVar<lite::Tensor>(scope, Out_name);
-  } else {
-    param_.Out = param_.Out_grad;
-  }
-
-  return true;
-}
-
-#endif
+// #ifdef LITE_WITH_TRAIN
+
+// bool ActivationGradOp::CheckShape() const {
+//   CHECK_OR_FALSE(param_.X_grad);
+//   CHECK_OR_FALSE(param_.Out_grad);
+//   return true;
+// }
+
+// bool ActivationGradOp::InferShape() const {
+//   param_.X_grad->Resize(param_.Out_grad->dims());
+//   return true;
+// }
+
+// bool ActivationGradOp::AttachImpl(const cpp::OpDesc& opdesc,
+//                                   lite::Scope* scope) {
+//   auto Out_grad_name = opdesc.Input(framework::GradVarName("Out")).front();
+//   auto X_grad_name = opdesc.Output(framework::GradVarName("X")).front();
+
+//   param_.Out_grad = GetVar<lite::Tensor>(scope, Out_grad_name);
+//   param_.X_grad = GetMutableVar<Tensor>(scope, X_grad_name);
+
+//   if (opdesc.HasInput("X")) {
+//     auto X_name = opdesc.Input("X").front();
+//     param_.X = GetVar<lite::Tensor>(scope, X_name);
+//   } else {
+//     param_.X = param_.X_grad;
+//   }
+
+//   if (opdesc.HasInput("Out")) {
+//     auto Out_name = opdesc.Input("Out").front();
+//     param_.Out = GetVar<lite::Tensor>(scope, Out_name);
+//   } else {
+//     param_.Out = param_.Out_grad;
+//   }
+
+//   return true;
+// }
+
+// #endif
 
 }  // namespace operators
 }  // namespace lite
@@ -139,6 +139,6 @@ REGISTER_LITE_OP(rsqrt, paddle::lite::operators::ActivationOp);
 REGISTER_LITE_OP(softsign, paddle::lite::operators::ActivationOp);
 REGISTER_LITE_OP(gelu, paddle::lite::operators::ActivationOp);
 
-#ifdef LITE_WITH_TRAIN
-REGISTER_LITE_OP(square_grad, paddle::lite::operators::ActivationGradOp);
-#endif
+// #ifdef LITE_WITH_TRAIN
+// REGISTER_LITE_OP(square_grad, paddle::lite::operators::ActivationGradOp);
+// #endif
diff --git a/lite/operators/activation_ops.h b/lite/operators/activation_ops.h
index 7ff91f7bcd2dce0fbdc4b5e8e4573ecc52387d72..87e1f8e72c74a9ac63eb83ca2f2f4c72f4d80e53 100644
--- a/lite/operators/activation_ops.h
+++ b/lite/operators/activation_ops.h
@@ -38,25 +38,26 @@ class ActivationOp : public OpLite {
   mutable operators::ActivationParam param_;
 };
 
-#ifdef LITE_WITH_TRAIN
-class ActivationGradOp : public OpLite {
- public:
-  explicit ActivationGradOp(const std::string& type) : OpLite(type) {}
+// #ifdef LITE_WITH_TRAIN
+// class ActivationGradOp : public OpLite {
+//  public:
+//   explicit ActivationGradOp(const std::string& type) : OpLite(type) {}
 
-  bool CheckShape() const override;
+//   bool CheckShape() const override;
 
-  bool InferShape() const override;
+//   bool InferShape() const override;
 
-  bool AttachImpl(const cpp::OpDesc& opdesc, lite::Scope* scope) override;
+//   bool AttachImpl(const cpp::OpDesc& opdesc, lite::Scope* scope) override;
 
-  void AttachKernel(KernelBase* kernel) override { kernel->SetParam(param_); }
+//   void AttachKernel(KernelBase* kernel) override { kernel->SetParam(param_);
+//   }
 
-  std::string DebugString() const override { return "activation_grad_op"; }
+//   std::string DebugString() const override { return "activation_grad_op"; }
 
- private:
-  mutable operators::ActivationGradParam param_;
-};
-#endif
+//  private:
+//   mutable operators::ActivationGradParam param_;
+// };
+// #endif
 
 }  // namespace operators
 }  // namespace lite
diff --git a/lite/operators/elementwise_ops.cc b/lite/operators/elementwise_ops.cc
index c5613ae52d3aadd6d863cadecac1870c40ed4cbf..3dc6f06955d421bc1f25994139cfee5dee9bc472 100644
--- a/lite/operators/elementwise_ops.cc
+++ b/lite/operators/elementwise_ops.cc
@@ -96,39 +96,39 @@ bool ElementwiseOp::AttachImpl(const cpp::OpDesc& opdesc, lite::Scope* scope) {
   return true;
 }
 
-#ifdef LITE_WITH_TRAIN
-bool ElementwiseGradExplicitOp::CheckShape() const {
-  CHECK_OR_FALSE(param_.Y);
-  CHECK_OR_FALSE(param_.X_grad);
-  CHECK_OR_FALSE(param_.Out_grad);
-  return true;
-}
+// #ifdef LITE_WITH_TRAIN
+// bool ElementwiseGradExplicitOp::CheckShape() const {
+//  CHECK_OR_FALSE(param_.Y);
+//  CHECK_OR_FALSE(param_.X_grad);
+//  CHECK_OR_FALSE(param_.Out_grad);
+//  return true;
+//}
 
-bool ElementwiseGradExplicitOp::InferShape() const {
-  param_.X_grad->Resize(param_.Out_grad->dims());
-  if (param_.Y_grad) param_.Y_grad->Resize(param_.Y->dims());
-  return true;
-}
+// bool ElementwiseGradExplicitOp::InferShape() const {
+//   param_.X_grad->Resize(param_.Out_grad->dims());
+//   if (param_.Y_grad) param_.Y_grad->Resize(param_.Y->dims());
+//   return true;
+// }
 
-bool ElementwiseGradExplicitOp::AttachImpl(const cpp::OpDesc& opdesc,
-                                           lite::Scope* scope) {
-  CHECK_EQ(opdesc.InputArgumentNames().size(), 2UL);
-  auto Y_name = opdesc.Input("Y").front();
-  auto Out_name = opdesc.Input(framework::GradVarName("Out")).front();
-  auto X_grad = opdesc.Output(framework::GradVarName("X")).front();
+// bool ElementwiseGradExplicitOp::AttachImpl(const cpp::OpDesc& opdesc,
+//                                            lite::Scope* scope) {
+//   CHECK_EQ(opdesc.InputArgumentNames().size(), 2UL);
+//   auto Y_name = opdesc.Input("Y").front();
+//   auto Out_name = opdesc.Input(framework::GradVarName("Out")).front();
+//   auto X_grad = opdesc.Output(framework::GradVarName("X")).front();
 
-  if (opdesc.Output(framework::GradVarName("Y")).size() > 0) {
-    auto Y_grad = opdesc.Output(framework::GradVarName("Y")).front();
-    param_.Y_grad = GetMutableVar<Tensor>(scope, Y_grad);
-  }
-  param_.Y = GetVar<lite::Tensor>(scope, Y_name);
-  param_.Out_grad = GetVar<lite::Tensor>(scope, Out_name);
-  param_.X_grad = GetMutableVar<lite::Tensor>(scope, X_grad);
-  param_.axis = opdesc.GetAttr<int>("axis");
+//   if (opdesc.Output(framework::GradVarName("Y")).size() > 0) {
+//     auto Y_grad = opdesc.Output(framework::GradVarName("Y")).front();
+//     param_.Y_grad = GetMutableVar<Tensor>(scope, Y_grad);
+//   }
+//   param_.Y = GetVar<lite::Tensor>(scope, Y_name);
+//   param_.Out_grad = GetVar<lite::Tensor>(scope, Out_name);
+//   param_.X_grad = GetMutableVar<lite::Tensor>(scope, X_grad);
+//   param_.axis = opdesc.GetAttr<int>("axis");
 
-  return true;
-}
-#endif
+//   return true;
+// }
+// #endif
 
 }  // namespace operators
 }  // namespace lite
@@ -141,7 +141,9 @@ REGISTER_LITE_OP(elementwise_mul, paddle::lite::operators::ElementwiseOp);
 REGISTER_LITE_OP(elementwise_max, paddle::lite::operators::ElementwiseOp);
 REGISTER_LITE_OP(elementwise_div, paddle::lite::operators::ElementwiseOp);
 
-#ifdef LITE_WITH_TRAIN
-REGISTER_LITE_OP(elementwise_sub_grad,
-                 paddle::lite::operators::ElementwiseGradExplicitOp);
-#endif
+// #ifdef LITE_WITH_TRAIN
+// REGISTER_LITE_OP(elementwise_sub_grad,
+//                  paddle::lite::operators::ElementwiseGradExplicitOp);
+// REGISTER_LITE_OP(elementwise_add_grad,
+//                  paddle::lite::operators::ElementwiseGradExplicitOp);
+// #endif
diff --git a/lite/operators/elementwise_ops.h b/lite/operators/elementwise_ops.h
index b86d35e282c893b422677395dffe871a0d7f829b..d888e3d1c14b5d3129e01d12c75e1f590c17f297 100644
--- a/lite/operators/elementwise_ops.h
+++ b/lite/operators/elementwise_ops.h
@@ -39,27 +39,29 @@ class ElementwiseOp : public OpLite {
   mutable operators::ElementwiseParam param_;
 };
 
-#ifdef LITE_WITH_TRAIN
-class ElementwiseGradExplicitOp : public OpLite {
- public:
-  explicit ElementwiseGradExplicitOp(const std::string& type) : OpLite(type) {}
+// #ifdef LITE_WITH_TRAIN
+// class ElementwiseGradExplicitOp : public OpLite {
+//  public:
+//   explicit ElementwiseGradExplicitOp(const std::string& type) : OpLite(type)
+//   {}
 
-  bool CheckShape() const override;
+//   bool CheckShape() const override;
 
-  bool InferShape() const override;
+//   bool InferShape() const override;
 
-  bool AttachImpl(const cpp::OpDesc& opdesc, lite::Scope* scope) override;
+//   bool AttachImpl(const cpp::OpDesc& opdesc, lite::Scope* scope) override;
 
-  void AttachKernel(KernelBase* kernel) override { kernel->SetParam(param_); }
+//   void AttachKernel(KernelBase* kernel) override { kernel->SetParam(param_);
+//   }
 
-  std::string DebugString() const override {
-    return "elementwise_grad_explicit_op";
-  }
+//   std::string DebugString() const override {
+//     return "elementwise_grad_explicit_op";
+//   }
 
- private:
-  mutable operators::ElementwiseGradParam param_;
-};
-#endif
+//  private:
+//   mutable operators::ElementwiseGradParam param_;
+// };
+// #endif
 
 }  // namespace operators
 }  // namespace lite
diff --git a/lite/operators/fusion_elementwise_activation_ops.cc b/lite/operators/fusion_elementwise_activation_ops.cc
index b82c6454b4d8e9ca1af45374ea05925cbbadf0ed..244394b95aafede6956bc548430f5c14f28ae910 100644
--- a/lite/operators/fusion_elementwise_activation_ops.cc
+++ b/lite/operators/fusion_elementwise_activation_ops.cc
@@ -100,8 +100,8 @@ REGISTER_LITE_OP(fusion_elementwise_max_activation,
 REGISTER_LITE_OP(fusion_elementwise_div_activation,
                  paddle::lite::operators::FusionElementwiseActivationOp);
 
-#ifdef LITE_WITH_TRAIN
-REGISTER_LITE_OP(
-    fusion_elementwise_sub_activation_grad,
-    paddle::lite::operators::FusionElementwiseActivationGradExplicitOp);
-#endif
+// #ifdef LITE_WITH_TRAIN
+// REGISTER_LITE_OP(
+//     fusion_elementwise_sub_activation_grad,
+//     paddle::lite::operators::FusionElementwiseActivationGradExplicitOp);
+// #endif
diff --git a/lite/operators/fusion_elementwise_activation_ops.h b/lite/operators/fusion_elementwise_activation_ops.h
index 1999ebd7220c81c313492ae106812c0eb755cb6e..db521284f0fc96c542fd5e7104b045f83f837f97 100644
--- a/lite/operators/fusion_elementwise_activation_ops.h
+++ b/lite/operators/fusion_elementwise_activation_ops.h
@@ -43,28 +43,29 @@ class FusionElementwiseActivationOp : public OpLite {
   mutable operators::FusionElementwiseActivationParam param_;
 };
 
-#ifdef LITE_WITH_TRAIN
-class FusionElementwiseActivationGradExplicitOp : public OpLite {
- public:
-  explicit FusionElementwiseActivationGradExplicitOp(const std::string& type)
-      : OpLite(type) {}
+// #ifdef LITE_WITH_TRAIN
+// class FusionElementwiseActivationGradExplicitOp : public OpLite {
+//  public:
+//   explicit FusionElementwiseActivationGradExplicitOp(const std::string& type)
+//       : OpLite(type) {}
 
-  bool CheckShape() const override;
+//   bool CheckShape() const override;
 
-  bool InferShape() const override;
+//   bool InferShape() const override;
 
-  bool AttachImpl(const cpp::OpDesc& opdesc, lite::Scope* scope) override;
+//   bool AttachImpl(const cpp::OpDesc& opdesc, lite::Scope* scope) override;
 
-  void AttachKernel(KernelBase* kernel) override { kernel->SetParam(param_); }
+//   void AttachKernel(KernelBase* kernel) override { kernel->SetParam(param_);
+//   }
 
-  std::string DebugString() const override {
-    return "fusion_elementwise_activation_grad_explicit_op";
-  }
+//   std::string DebugString() const override {
+//     return "fusion_elementwise_activation_grad_explicit_op";
+//   }
 
- private:
-  mutable operators::FusionElementwiseActivationGradParam param_;
-};
-#endif
+//  private:
+//   mutable operators::FusionElementwiseActivationGradParam param_;
+// };
+// #endif
 
 }  // namespace operators
 }  // namespace lite
diff --git a/lite/operators/mean_grad_op.cc b/lite/operators/mean_grad_op.cc
new file mode 100644
index 0000000000000000000000000000000000000000..fd17cac14fca153499a52e93f6f09ea44ea9a559
--- /dev/null
+++ b/lite/operators/mean_grad_op.cc
@@ -0,0 +1,52 @@
+// Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "lite/operators/mean_grad_op.h"
+#include <vector>
+#include "lite/core/op_lite.h"
+#include "lite/core/op_registry.h"
+
+namespace paddle {
+namespace lite {
+namespace operators {
+
+bool MeanGradOp::CheckShape() const {
+  CHECK_OR_FALSE(param_.X);
+  CHECK_OR_FALSE(param_.Out_grad);
+  CHECK_OR_FALSE(param_.X_grad);
+  return true;
+}
+
+bool MeanGradOp::InferShape() const {
+  param_.X_grad->Resize(param_.X->dims());
+  return true;
+}
+
+bool MeanGradOp::AttachImpl(const cpp::OpDesc& opdesc, lite::Scope* scope) {
+  CHECK_EQ(opdesc.InputArgumentNames().size(), 2UL);
+  auto X_name = opdesc.Input("X").front();
+  auto Out_grad_name = opdesc.Input("Out@GRAD").front();
+  auto X_grad_name = opdesc.Output("X@GRAD").front();
+
+  param_.X = GetVar<lite::Tensor>(scope, X_name);
+  param_.Out_grad = GetVar<lite::Tensor>(scope, Out_grad_name);
+  param_.X_grad = GetMutableVar<Tensor>(scope, X_grad_name);
+  return true;
+}
+
+}  // namespace operators
+}  // namespace lite
+}  // namespace paddle
+
+REGISTER_LITE_OP(mean_grad, paddle::lite::operators::MeanGradOp);
diff --git a/lite/operators/mean_grad_op.h b/lite/operators/mean_grad_op.h
new file mode 100644
index 0000000000000000000000000000000000000000..1bd604518bfc088fc45566e393fd997ae4eed06e
--- /dev/null
+++ b/lite/operators/mean_grad_op.h
@@ -0,0 +1,44 @@
+// Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#pragma once
+#include <string>
+#include "lite/core/op_lite.h"
+#include "lite/core/op_registry.h"
+
+namespace paddle {
+namespace lite {
+namespace operators {
+
+class MeanGradOp : public OpLite {
+ public:
+  explicit MeanGradOp(const std::string &type) : OpLite(type) {}
+
+  bool CheckShape() const override;
+
+  bool InferShape() const override;
+
+  bool AttachImpl(const cpp::OpDesc &op_desc, lite::Scope *scope) override;
+
+  void AttachKernel(KernelBase *kernel) override { kernel->SetParam(param_); }
+
+  std::string DebugString() const override { return "mean_grad"; }
+
+ private:
+  mutable operators::MeanGradParam param_;
+};
+
+}  // namespace operators
+}  // namespace lite
+}  // namespace paddle
diff --git a/lite/operators/mean_op.cc b/lite/operators/mean_op.cc
index 33ad7ed7fe1c2c89339a689d4a6316d85307d871..618e9001db056b935de6aef8feff9125155d0e1a 100644
--- a/lite/operators/mean_op.cc
+++ b/lite/operators/mean_op.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserved.
+// Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+#include "lite/operators/mean_op.h"
+#include <vector>
 #include "lite/core/op_lite.h"
 #include "lite/core/op_registry.h"
 
@@ -19,82 +21,28 @@ namespace paddle {
 namespace lite {
 namespace operators {
 
-class MeanOp : public OpLite {
- public:
-  explicit MeanOp(const std::string& type) : OpLite(type) {}
+bool MeanOp::CheckShape() const {
+  CHECK_OR_FALSE(param_.X);
+  CHECK_OR_FALSE(param_.Out);
+  return true;
+}
 
-  bool CheckShape() const override {
-    CHECK_OR_FALSE(param_.X);
-    CHECK_OR_FALSE(param_.Out);
-    return true;
-  }
+bool MeanOp::InferShape() const {
+  param_.Out->Resize(std::vector<int64_t>{1});
+  return true;
+}
 
-  bool InferShape() const override {
-    param_.Out->Resize(std::vector<int64_t>{1});
-    return true;
-  }
+bool MeanOp::AttachImpl(const cpp::OpDesc& opdesc, lite::Scope* scope) {
+  auto X_name = opdesc.Input("X").front();
+  auto Out_name = opdesc.Output("Out").front();
 
-  bool AttachImpl(const cpp::OpDesc& opdesc, lite::Scope* scope) override {
-    auto X_name = opdesc.Input("X").front();
-    auto Out_name = opdesc.Output("Out").front();
-
-    param_.X = GetVar<lite::Tensor>(scope, X_name);
-    param_.Out = GetMutableVar<Tensor>(scope, Out_name);
-    return true;
-  }
-
-  void AttachKernel(KernelBase* kernel) override { kernel->SetParam(param_); }
-
-  std::string DebugString() const override { return "mean"; }
-
- private:
-  mutable operators::MeanParam param_;
-};
-
-#ifdef LITE_WITH_TRAIN
-class MeanGradOp : public OpLite {
- public:
-  explicit MeanGradOp(const std::string& type) : OpLite(type) {}
-
-  bool CheckShape() const override {
-    CHECK_OR_FALSE(param_.X);
-    CHECK_OR_FALSE(param_.Out_grad);
-    CHECK_OR_FALSE(param_.X_grad);
-    return true;
-  }
-
-  bool InferShape() const override {
-    param_.X_grad->Resize(param_.X->dims());
-    // param_.X_grad->set_lod(param_.X->lod());
-    return true;
-  }
-
-  bool AttachImpl(const cpp::OpDesc& opdesc, lite::Scope* scope) override {
-    CHECK_EQ(opdesc.InputArgumentNames().size(), 2UL);
-    auto X_name = opdesc.Input("X").front();
-    auto Out_grad_name = opdesc.Input(framework::GradVarName("Out")).front();
-    auto X_grad_name = opdesc.Output(framework::GradVarName("X")).front();
-
-    param_.X = GetVar<lite::Tensor>(scope, X_name);
-    param_.Out_grad = GetVar<lite::Tensor>(scope, Out_grad_name);
-    param_.X_grad = GetMutableVar<Tensor>(scope, X_grad_name);
-    return true;
-  }
-
-  void AttachKernel(KernelBase* kernel) override { kernel->SetParam(param_); }
-
-  std::string DebugString() const override { return "mean_grad"; }
-
- private:
-  mutable operators::MeanGradParam param_;
-};
-#endif
+  param_.X = GetVar<lite::Tensor>(scope, X_name);
+  param_.Out = GetMutableVar<Tensor>(scope, Out_name);
+  return true;
+}
 
 }  // namespace operators
 }  // namespace lite
 }  // namespace paddle
 
 REGISTER_LITE_OP(mean, paddle::lite::operators::MeanOp);
-#ifdef LITE_WITH_TRAIN
-REGISTER_LITE_OP(mean_grad, paddle::lite::operators::MeanGradOp);
-#endif
diff --git a/lite/operators/mean_op.h b/lite/operators/mean_op.h
new file mode 100644
index 0000000000000000000000000000000000000000..8526842f93cb1d01debad9c6cb28ec28b98e43e9
--- /dev/null
+++ b/lite/operators/mean_op.h
@@ -0,0 +1,44 @@
+// Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#pragma once
+#include <string>
+#include "lite/core/op_lite.h"
+#include "lite/core/op_registry.h"
+
+namespace paddle {
+namespace lite {
+namespace operators {
+
+class MeanOp : public OpLite {
+ public:
+  explicit MeanOp(const std::string &type) : OpLite(type) {}
+
+  bool CheckShape() const override;
+
+  bool InferShape() const override;
+
+  void AttachKernel(KernelBase *kernel) override { kernel->SetParam(param_); }
+
+  bool AttachImpl(const cpp::OpDesc &op_desc, lite::Scope *scope) override;
+
+  std::string DebugString() const override { return "mean"; }
+
+ private:
+  mutable operators::MeanParam param_;
+};
+
+}  // namespace operators
+}  // namespace lite
+}  // namespace paddle
diff --git a/lite/tests/kernels/CMakeLists.txt b/lite/tests/kernels/CMakeLists.txt
index 6d63b7054176fae6d2c88cf2e330fce2c6f7eb6f..79005151caac88c44e10581655c9704015dffe8f 100644
--- a/lite/tests/kernels/CMakeLists.txt
+++ b/lite/tests/kernels/CMakeLists.txt
@@ -60,6 +60,9 @@ if(LITE_BUILD_EXTRA)
     lite_cc_test(test_kernel_lookup_table_compute SRCS lookup_table_compute_test.cc DEPS arena_framework ${xpu_kernels} ${npu_kernels} ${bm_kernels} ${x86_kernels} ${cuda_kernels} ${arm_kernels} ${lite_ops} ${host_kernels})
     lite_cc_test(test_kernel_lookup_table_dequant_compute SRCS lookup_table_dequant_compute_test.cc DEPS arena_framework ${xpu_kernels} ${npu_kernels} ${bm_kernels} ${x86_kernels} ${cuda_kernels} ${arm_kernels} ${lite_ops} ${host_kernels})
     lite_cc_test(test_kernel_gather_compute SRCS gather_compute_test.cc DEPS arena_framework ${xpu_kernels} ${npu_kernels} ${x86_kernels} ${bm_kernels} ${cuda_kernels} ${arm_kernels} ${lite_ops} ${host_kernels})
+    # for training kernel
+    lite_cc_test(test_kernel_mean_compute SRCS mean_compute_test.cc DEPS arena_framework ${xpu_kernels} ${npu_kernels} ${x86_kernels} ${cuda_kernels} ${arm_kernels} ${lite_ops} ${host_kernels})
+
 endif()
     lite_cc_test(test_kernel_pad2d_compute SRCS  pad2d_compute_test.cc DEPS arena_framework ${xpu_kernels} ${npu_kernels} ${bm_kernels} ${x86_kernels} ${cuda_kernels} ${arm_kernels} ${lite_ops} ${host_kernels})
     lite_cc_test(test_kernel_prior_box_compute SRCS  prior_box_compute_test.cc DEPS arena_framework ${xpu_kernels} ${npu_kernels} ${bm_kernels}  ${x86_kernels} ${cuda_kernels} ${arm_kernels} ${lite_ops} ${host_kernels})
diff --git a/lite/tests/kernels/mean_compute_test.cc b/lite/tests/kernels/mean_compute_test.cc
new file mode 100644
index 0000000000000000000000000000000000000000..71eb86a6c15a77af92dc2b9c5da4fa2eb6aba406
--- /dev/null
+++ b/lite/tests/kernels/mean_compute_test.cc
@@ -0,0 +1,154 @@
+// Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <gtest/gtest.h>
+#include "lite/api/paddle_use_kernels.h"
+#include "lite/api/paddle_use_ops.h"
+#include "lite/core/arena/framework.h"
+#include "lite/tests/utils/fill_data.h"
+
+namespace paddle {
+namespace lite {
+
+class MeanComputeTester : public arena::TestCase {
+ protected:
+  DDim input_dims_{{2, 5}};
+  std::string input_ = "x";
+  std::string output_ = "out";
+
+ public:
+  MeanComputeTester(const Place& place,
+                    const std::string& alias,
+                    const DDim& input_dims)
+      : TestCase(place, alias), input_dims_(input_dims) {}
+
+  void RunBaseline(Scope* scope) override {
+    auto input = scope->FindTensor(input_);
+    auto output = scope->NewTensor(output_);
+
+    std::vector<int64_t> out_dims{1};
+    output->Resize(out_dims);
+
+    auto input_data = input->data<float>();
+    auto output_data = output->mutable_data<float>();
+
+    int x_size = input_dims_.production();
+    float sum = 0;
+    for (int i = 0; i < x_size; i++) {
+      sum += input_data[i];
+    }
+    output_data[0] = sum / x_size;
+  }
+
+  void PrepareOpDesc(cpp::OpDesc* op_desc) {
+    op_desc->SetType("mean");
+    op_desc->SetInput("X", {input_});
+    op_desc->SetOutput("Out", {output_});
+  }
+
+  void PrepareData() override {
+    std::vector<float> input(input_dims_.production());
+    fill_data_rand(input.data(), -1.f, 1.f, input_dims_.production());
+    SetCommonTensor(input_, input_dims_, input.data());
+  }
+};
+
+void TestNormalCase(Place place, float abs_error = 2e-5) {
+  LOG(INFO) << "Test Mean";
+  for (std::vector<int64_t> dims : std::vector<std::vector<int64_t>>{
+           {5}, {4, 5}, {3, 4, 5}, {2, 3, 4, 5}}) {
+    std::unique_ptr<arena::TestCase> tester(
+        new MeanComputeTester(place, "def", DDim(dims)));
+    arena::Arena arena(std::move(tester), place, abs_error);
+    arena.TestPrecision();
+  }
+}
+
+#ifdef LITE_WITH_TRAIN
+class MeanGradComputeTester : public arena::TestCase {
+ protected:
+  DDim input_dims_{{2, 5}};
+  DDim output_grad_dims_{{1}};
+  std::string input_ = "x";
+  std::string input_grad_ = "x_grad";
+  std::string output_grad_ = "out_grad";
+
+ public:
+  MeanGradComputeTester(const Place& place,
+                        const std::string& alias,
+                        const DDim& input_dims)
+      : TestCase(place, alias), input_dims_(input_dims) {}
+
+  void RunBaseline(Scope* scope) override {
+    auto input = scope->FindTensor(input_);
+    auto output_grad = scope->FindTensor(output_grad_);
+    auto input_grad = scope->NewTensor(input_grad_);
+
+    input_grad->Resize(input_dims_);
+
+    auto input_data = input->data<float>();
+    auto output_grad_data = output_grad->data<float>();
+    auto input_grad_data = input_grad->mutable_data<float>();
+
+    int x_size = input_dims_.production();
+    float d_x = output_grad_data[0] / x_size;
+
+    for (int i = 0; i < x_size; i++) {
+      input_grad_data[i] = d_x;
+    }
+  }
+
+  void PrepareOpDesc(cpp::OpDesc* op_desc) {
+    op_desc->SetType("mean_grad");
+    op_desc->SetInput("X", {input_});
+    op_desc->SetInput("Out@GRAD", {output_grad_});
+    op_desc->SetOutput("X@GRAD", {input_grad_});
+  }
+
+  void PrepareData() override {
+    std::vector<float> input(input_dims_.production());
+    fill_data_rand(input.data(), -1.f, 1.f, input_dims_.production());
+    SetCommonTensor(input_, input_dims_, input.data());
+
+    std::vector<float> output_grad(1);
+    fill_data_rand(output_grad.data(), -1.f, 1.f, 1);
+    SetCommonTensor(output_grad_, output_grad_dims_, output_grad.data());
+  }
+};
+
+void TestGradNormalCase(Place place, float abs_error = 2e-5) {
+  LOG(INFO) << "Test Mean Grad";
+  for (std::vector<int64_t> dims : std::vector<std::vector<int64_t>>{
+           {5}, {4, 5}, {3, 4, 5}, {2, 3, 4, 5}}) {
+    std::unique_ptr<arena::TestCase> tester(
+        new MeanGradComputeTester(place, "def", DDim(dims)));
+    arena::Arena arena(std::move(tester), place, abs_error);
+    arena.TestPrecision();
+  }
+}
+#endif
+
+TEST(Mean, precision) {
+#ifdef LITE_WITH_ARM
+  float abs_error = 2e-5;
+  Place place(TARGET(kARM));
+  TestNormalCase(place, abs_error);
+#ifdef LITE_WITH_TRAIN
+  TestGradNormalCase(place, abs_error);
+#endif
+#endif
+}
+
+}  // namespace lite
+}  // namespace paddle
diff --git a/lite/tools/ci_build.sh b/lite/tools/ci_build.sh
index a4223215d5c10d6eda6dc54ec57981d4f1954e40..6105b138c6789544716d3908dd1bf4847ba81c9a 100755
--- a/lite/tools/ci_build.sh
+++ b/lite/tools/ci_build.sh
@@ -594,6 +594,7 @@ function cmake_arm {
         -DLITE_WITH_LIGHT_WEIGHT_FRAMEWORK=ON \
         -DWITH_TESTING=ON \
         -DLITE_BUILD_EXTRA=ON \
+        -DLITE_WITH_TRAIN=ON \
         -DARM_TARGET_OS=$1 -DARM_TARGET_ARCH_ABI=$2 -DARM_TARGET_LANG=$3
 }
 
diff --git a/lite/tools/cmake_tools/parse_op_registry.py b/lite/tools/cmake_tools/parse_op_registry.py
index 7eb3337ed87b708102b2032de9a279fcae2d321c..44ee09c28ff70ada782b9393f4fc0d5c07943b2c 100644
--- a/lite/tools/cmake_tools/parse_op_registry.py
+++ b/lite/tools/cmake_tools/parse_op_registry.py
@@ -45,8 +45,6 @@ for path in paths:
     op_parser = RegisterLiteOpParser(str_info)
     ops = op_parser.parse()
     for op in ops:
-        if "_grad" in op: 
-            continue
         if tailored == "ON":
             if op not in minlines: continue
         out = "USE_LITE_OP(%s);" % op