diff --git a/paddle/framework/CMakeLists.txt b/paddle/framework/CMakeLists.txt
index 7febaaa52729bf8af808d10aab5d74f989f895cb..c9a50d8968e56885e100cf287b8a0417ce526eb0 100644
--- a/paddle/framework/CMakeLists.txt
+++ b/paddle/framework/CMakeLists.txt
@@ -30,7 +30,7 @@ add_custom_target(framework_py_proto_init ALL COMMAND ${CMAKE_COMMAND} -E touch
 add_dependencies(framework_py_proto framework_py_proto_init)
 
 cc_library(net SRCS net.cc DEPS op_registry)
-cc_test(net_op_test SRCS net_op_test.cc DEPS net add_op mul_op sigmoid_op softmax_op fc_op)
+cc_test(net_op_test SRCS net_op_test.cc DEPS net)
 
 cc_library(backward SRCS backward.cc DEPS net)
 cc_test(backward_test SRCS backward_test.cc DEPS backward)
diff --git a/paddle/framework/net.h b/paddle/framework/net.h
index 089c1355951f59d51db16d4b4bdce4282d6e5c25..b584dd578f3b39af55c1be215a23c9ac46424fcb 100644
--- a/paddle/framework/net.h
+++ b/paddle/framework/net.h
@@ -68,9 +68,18 @@ class NetOp : public OperatorBase {
    */
   void AddOp(const std::shared_ptr<OperatorBase>& op) {
     PADDLE_ENFORCE(!add_op_done_, "Cannot AddOp when this network is sealed");
+    PADDLE_ENFORCE(op != nullptr, "Cannot Insert Null op");
     ops_.push_back(op);
   }
 
+  void InsertOp(size_t pos, const std::shared_ptr<OperatorBase>& op) {
+    PADDLE_ENFORCE(!add_op_done_,
+                   "Cannot InsertOp when this network is sealed");
+    PADDLE_ENFORCE(op != nullptr, "Cannot Insert Null op");
+    PADDLE_ENFORCE(pos <= ops_.size(), "Out of range");
+    ops_.insert(ops_.begin() + pos, op);
+  }
+
   void CompleteAddOp(bool calculate = true);
 
   std::string DebugString() const override;
diff --git a/paddle/framework/net_op_test.cc b/paddle/framework/net_op_test.cc
index 8048311fe54ee1827fb5b91577478a1d30803e43..4b733e958e48a2e5f072d90f8e83c430bc8251d9 100644
--- a/paddle/framework/net_op_test.cc
+++ b/paddle/framework/net_op_test.cc
@@ -3,11 +3,6 @@
 #include <paddle/framework/op_registry.h>
 #include <paddle/framework/operator.h>
 
-USE_OP(add_two);
-USE_OP(mul);
-USE_OP(sigmoid);
-USE_OP(softmax);
-
 namespace paddle {
 namespace framework {
 
@@ -26,6 +21,13 @@ class TestOp : public OperatorBase {
   }
 };
 
+class EmptyOp : public OperatorBase {
+ public:
+  void InferShape(const std::shared_ptr<Scope>& scope) const override {}
+  void Run(const std::shared_ptr<Scope>& scope,
+           const platform::DeviceContext& dev_ctx) const override {}
+};
+
 template <typename T>
 void AssertSameVectorWithoutOrder(const std::vector<T>& expected,
                                   const std::vector<T>& actual) {
@@ -72,20 +74,17 @@ TEST(OpKernel, all) {
   ASSERT_THROW(net->AddOp(op2), paddle::platform::EnforceNotMet);
 }
 
-//! TODO(yuyang18): Refine Backward Op.
-// TEST(AddBackwardOp, TestGradOp) {
-//  auto net = std::make_shared<NetOp>();
-//  ASSERT_NE(net, nullptr);
-//  net->AddOp(framework::OpRegistry::CreateOp("mul", {"X", "Y"}, {"Out"}, {}));
-//  net->AddOp(
-//      framework::OpRegistry::CreateOp("add_two", {"X", "Y"}, {"Out"}, {}));
-//  net->AddOp(framework::OpRegistry::CreateOp("add_two", {"X", "Y"}, {""},
-//  {}));
-//  auto grad_ops = AddBackwardOp(net);
-//  for (auto& op : grad_ops->ops_) {
-//    op->DebugString();
-//  }
-//}
+TEST(Net, insert_op) {
+  NetOp net;
+  auto op1 = std::make_shared<EmptyOp>();
+  op1->inputs_ = {"x", "w1", "b1"};
+  op1->outputs_ = {"y"};
+  net.AddOp(op1);
+  net.InsertOp(0, op1);
+  ASSERT_EQ(2UL, net.ops_.size());
+  net.InsertOp(2, op1);
+  ASSERT_EQ(3UL, net.ops_.size());
+}
 
 }  // namespace framework
 }  // namespace paddle