diff --git a/src/config/api-server/vnc_cfg_api_server.py b/src/config/api-server/vnc_cfg_api_server.py
index fb14f32b0d6..9139afc9f49 100644
--- a/src/config/api-server/vnc_cfg_api_server.py
+++ b/src/config/api-server/vnc_cfg_api_server.py
@@ -10,6 +10,10 @@
 monkey.patch_all()
 from gevent import hub
 
+# from neutron plugin to api server, the request URL could be large. fix the const
+import gevent.pywsgi
+gevent.pywsgi.MAX_REQUEST_LINE = 65535
+
 import sys
 reload(sys)
 sys.setdefaultencoding('UTF8')