diff --git a/python/paddle_serving_client/__init__.py b/python/paddle_serving_client/__init__.py
index f400336986780822cffa48927387658c7c13148c..73f67cb82b4817ab3f9fc12269c0cc61ee8eab05 100644
--- a/python/paddle_serving_client/__init__.py
+++ b/python/paddle_serving_client/__init__.py
@@ -104,7 +104,7 @@ class Client(object):
         predictor_sdk = SDKConfig()
         predictor_sdk.set_server_endpoints(endpoints)
         sdk_desc = predictor_sdk.gen_desc()
-        self.client_handle_.create_predictor_by_desc(sdk_desc)
+        self.client_handle_.create_predictor_by_desc(sdk_desc.SerializeToString())
 
     def get_feed_names(self):
         return self.feed_names_