diff --git a/pilot/base_modules/agent/controller.py b/pilot/base_modules/agent/controller.py
index 47532a66b..92ca2f477 100644
--- a/pilot/base_modules/agent/controller.py
+++ b/pilot/base_modules/agent/controller.py
@@ -69,8 +69,10 @@ async def agent_hub_update(update_param: PluginHubParam = Body()):
     logger.info(f"agent_hub_update:{update_param.__dict__}")
     try:
         agent_hub = AgentHub(PLUGINS_DIR)
+        branch = update_param.branch if update_param.branch is not None and len(update_param.branch) > 0 else  "main"
+        authorization = update_param.authorization if update_param.branch is not None and len(update_param.branch) > 0 else None
         agent_hub.refresh_hub_from_git(
-            update_param.url, update_param.branch, update_param.authorization
+            update_param.url, branch, authorization
         )
         return Result.succ(None)
     except Exception as e:
diff --git a/pilot/base_modules/agent/hub/agent_hub.py b/pilot/base_modules/agent/hub/agent_hub.py
index 3af9c722e..29cd49fc3 100644
--- a/pilot/base_modules/agent/hub/agent_hub.py
+++ b/pilot/base_modules/agent/hub/agent_hub.py
@@ -125,7 +125,7 @@ class AgentHub:
         my_plugin_entity.version = hub_plugin.version
         return my_plugin_entity
 
-    def refresh_hub_from_git(self, github_repo: str = None, branch_name: str = None, authorization: str = None):
+    def refresh_hub_from_git(self, github_repo: str = None, branch_name: str = "main", authorization: str = None):
         logger.info("refresh_hub_by_git start!")
         update_from_git(self.temp_hub_file_path, github_repo, branch_name, authorization)
         git_plugins = scan_plugins(self.temp_hub_file_path)