diff --git a/paddle/framework/grad_op_builder.cc b/paddle/framework/grad_op_builder.cc
index 6d032fb78f099f5142d64e531d1a03c10ed5e68e..0121d999613376615ac3bb6b30e4743c5b613d36 100644
--- a/paddle/framework/grad_op_builder.cc
+++ b/paddle/framework/grad_op_builder.cc
@@ -76,7 +76,7 @@ static void TransOpArg(const OperatorBase* src_op, OperatorBase* dst_op,
 }
 
 OperatorBase* BuildGradOp(const OperatorBase* op) {
-  std::string grad_op_type = OpRegistry::grad_ops().at(op->type_);
+  const std::string& grad_op_type = OpRegistry::grad_ops().at(op->Type());
   OperatorBase* grad_op = OpRegistry::op_creators().at(grad_op_type)();
   grad_op->type_ = grad_op_type;
   grad_op->attrs_ = op->attrs_;