diff --git a/python/paddle_serving_server/web_service.py b/python/paddle_serving_server/web_service.py
index 8f859c2cebc836d50edb7904f31b4bd4f7e8d98f..ea43c8cb18731f60d905ccbe4bada605709d9c11 100755
--- a/python/paddle_serving_server/web_service.py
+++ b/python/paddle_serving_server/web_service.py
@@ -122,7 +122,7 @@ class WebService(object):
                               processes=1)
 
     def get_app_instance(self):
-        return app_instance
+        return self.app_instance
 
     def preprocess(self, feed=[], fetch=[]):
         return feed, fetch
diff --git a/python/paddle_serving_server_gpu/web_service.py b/python/paddle_serving_server_gpu/web_service.py
index 4c887f0e3048031b97eb0deda0662adeaddeb559..0eff9c72df84b30ded7dbc7c2e82a96bbd591162 100644
--- a/python/paddle_serving_server_gpu/web_service.py
+++ b/python/paddle_serving_server_gpu/web_service.py
@@ -171,7 +171,7 @@ class WebService(object):
                               processes=1)
 
     def get_app_instance(self):
-        return app_instance
+        return self.app_instance
 
     def preprocess(self, feed=[], fetch=[]):
         return feed, fetch