diff --git a/paddle/fluid/operators/activation_op.cc b/paddle/fluid/operators/activation_op.cc
index acffb5d171d7bf52b57c1592c27966df95a37e23..7db6c6e6769c9929e1ce12c90886130058a4a1c5 100755
--- a/paddle/fluid/operators/activation_op.cc
+++ b/paddle/fluid/operators/activation_op.cc
@@ -36,20 +36,6 @@ static constexpr bool CanInplaceAct() {
   return GradFunctor::FwdDeps() == kDepOut || GradFunctor::FwdDeps() == kNoDeps;
 }
 
-std::unique_ptr<std::unordered_set<std::string>> GetInplaceOpSet() {
-  std::unique_ptr<std::unordered_set<std::string>> ret(
-      new std::unordered_set<std::string>());
-#define INSERT_INTO_INPLACE_OP_SET(op_type, __omitted, fwd_functor, \
-                                   bwd_functor)                     \
-  if (CanInplaceAct<bwd_functor<float>>()) {                        \
-    ret->insert(#op_type);                                          \
-  }
-
-  FOR_EACH_ACTIVATION_OP(INSERT_INTO_INPLACE_OP_SET);
-#undef INSERT_INTO_INPLACE_OP_SET
-  return ret;
-}
-
 #define REGISTER_ACTIVATION_OP_MAKER(OP_NAME, OP_COMMENT)                    \
   class OP_NAME##OpMaker                                                     \
       : public ::paddle::framework::OpProtoAndCheckerMaker {                 \
diff --git a/paddle/fluid/operators/activation_op.h b/paddle/fluid/operators/activation_op.h
index 1739aa2924d2e7fd97d07a2a39ba8323002f41c3..b4d01dfc6b93caab148ace1d7a70488fd628394f 100644
--- a/paddle/fluid/operators/activation_op.h
+++ b/paddle/fluid/operators/activation_op.h
@@ -49,21 +49,6 @@ enum ActBwdOpFwdDeps {
   kDepXOut = 0x03
 };
 
-std::unique_ptr<std::unordered_set<std::string>> GetInplaceOpSet();
-
-static bool IsInplace(const std::string& op) {
-  static auto InplaceOpSet = GetInplaceOpSet();
-  bool inplace = InplaceOpSet->count(op);
-  // for op_grad
-  const int kGradSuffixLen = 4;
-  if (op.size() > kGradSuffixLen &&
-      op.compare(op.size() - kGradSuffixLen - 1, kGradSuffixLen, "grad")) {
-    inplace =
-        InplaceOpSet->count(op.substr(0, op.size() - (kGradSuffixLen + 1)));
-  }
-  return inplace;
-}
-
 /* The following operator can be used to process SelectedRows, because the
  * output of those operator for zero is zero too.
  */
diff --git a/paddle/fluid/pybind/pybind.cc b/paddle/fluid/pybind/pybind.cc
index 5db8b4df99adac35048997f24c86092838ca9b20..c0aeb82b7b87f6e2f52c3dd778a397d15a700b44 100644
--- a/paddle/fluid/pybind/pybind.cc
+++ b/paddle/fluid/pybind/pybind.cc
@@ -1080,9 +1080,6 @@ All parameter, weight, gradient are variables in Paddle.
            },
            py::return_value_policy::take_ownership);
 
-  m.def("IsInplace",
-        [](std::string op) -> bool { return operators::IsInplace(op); });
-
   m.def("op_support_gpu", OpSupportGPU);
 #ifdef PADDLE_WITH_CUDA
   m.def("get_cuda_device_count", platform::GetCUDADeviceCount);