diff --git a/webapp/controller/ShopController.class.php b/webapp/controller/ShopController.class.php
index ff0041f5..56338d4a 100644
--- a/webapp/controller/ShopController.class.php
+++ b/webapp/controller/ShopController.class.php
@@ -1178,7 +1178,7 @@ class ShopController extends BaseAuthedController
                 return;
             }
         } else {
-            $gold = 500;
+            $gold = 0;
             if ($gold < $cost) {
                 $this->_rspErr(2, 'gold is not enough');
                 return;