diff --git a/cyberpanel_upgrade.sh b/cyberpanel_upgrade.sh
index 311114562..457a8c0b2 100644
--- a/cyberpanel_upgrade.sh
+++ b/cyberpanel_upgrade.sh
@@ -128,7 +128,7 @@ if [ $SERVER_OS = "Ubuntu" ] ; then
   pip3 install virtualenv
   check_return
 else
-  pip3.6 install virtualenv
+  pip3.6 install virtualenv==16.7.9
   check_return
 fi