diff --git a/discord/ext/commands/bot.py b/discord/ext/commands/bot.py
index 5b872f88c..048b2f4dc 100644
--- a/discord/ext/commands/bot.py
+++ b/discord/ext/commands/bot.py
@@ -809,7 +809,7 @@ class BotBase(GroupMixin):
             ret = [p for p in ret if p]
 
         if not ret:
-            raise ClientException('invalid prefix (could be an empty string, empty list, or None)')
+            raise discord.ClientException('invalid prefix (could be an empty string, empty list, or None)')
 
         return ret