diff --git a/appmanage/api/utils/docker.py b/appmanage/api/utils/docker.py
index a7fda14b..4c6473fa 100644
--- a/appmanage/api/utils/docker.py
+++ b/appmanage/api/utils/docker.py
@@ -89,7 +89,7 @@ def check_app_id(app_id):
     if app_id == None:
         code = const.ERROR_CLIENT_PARAM_BLANK
         message = "AppID is null"
-    elif re.match('^[a-zA-Z0-9]+_[a-z0-9]+$', app_id):
+    elif re.match('^[a-z0-9]+_[a-z0-9]+$', app_id):
         code = const.ERROR_CLIENT_PARAM_Format
         message = "APP name can only be composed of numbers and lowercase letters"
     myLogger.info_logger(code)