diff --git a/metagpt/tools/__init__.py b/metagpt/tools/__init__.py
index 4b27be287..35fa04658 100644
--- a/metagpt/tools/__init__.py
+++ b/metagpt/tools/__init__.py
@@ -19,7 +19,7 @@ class SearchEngineType(Enum):
     DIRECT_GOOGLE = "google"
     DUCK_DUCK_GO = "ddg"
     CUSTOM_ENGINE = "custom"
-    Bing = "bing"
+    BING = "bing"
 
 
 class WebBrowserEngineType(Enum):