diff --git a/python/paddle_serving_server/web_service.py b/python/paddle_serving_server/web_service.py
index cfd75b88ad7ef395a97bc7126404581ac089db5b..f8c43707660e08e1bc44fdd62e40e20523f6cb6d 100755
--- a/python/paddle_serving_server/web_service.py
+++ b/python/paddle_serving_server/web_service.py
@@ -116,10 +116,10 @@ class WebService(object):
         self.app_instance = app_instance
 
     def run_flask(self):
-        app_instance.run(host="0.0.0.0",
-                         port=self.port,
-                         threaded=False,
-                         processes=1)
+        self.app_instance.run(host="0.0.0.0",
+                              port=self.port,
+                              threaded=False,
+                              processes=1)
 
     def get_app_instance(self):
         return self.app_instance
diff --git a/python/paddle_serving_server_gpu/web_service.py b/python/paddle_serving_server_gpu/web_service.py
index 806ea85ba52fc3e19f8c2893d98598db0f944934..e64e73197d02a80e43bbc77a7589ab43efe2f244 100644
--- a/python/paddle_serving_server_gpu/web_service.py
+++ b/python/paddle_serving_server_gpu/web_service.py
@@ -166,10 +166,10 @@ class WebService(object):
         self.app_instance = app_instance
 
     def run_flask(self):
-        app_instance.run(host="0.0.0.0",
-                         port=self.port,
-                         threaded=False,
-                         processes=1)
+        self.app_instance.run(host="0.0.0.0",
+                              port=self.port,
+                              threaded=False,
+                              processes=1)
 
     def get_app_instance(self):
         return app_instance