diff --git a/paddle/fluid/operators/activation_op.cc b/paddle/fluid/operators/activation_op.cc
index 60b3dbb25c45eab93101f266a1438a88d98a5c64..69ae210148c7309822126a81d3e4d767442fc0f2 100644
--- a/paddle/fluid/operators/activation_op.cc
+++ b/paddle/fluid/operators/activation_op.cc
@@ -574,7 +574,8 @@ class Relu6OpMaker : public framework::OpProtoAndCheckerMaker {
         .SetDefault(6.0f);
     AddAttr<bool>("use_mkldnn",
                   "(bool, default false) Only used in mkldnn kernel")
-        .SetDefault(false);
+        .SetDefault(false)
+        .AsExtra();
     AddComment(R"DOC(
 Relu6 Activation Operator.