diff --git a/library/think/url.php b/library/think/url.php
index 53088d4a..b8d2f254 100644
--- a/library/think/url.php
+++ b/library/think/url.php
@@ -93,7 +93,7 @@ class Url
                 $suffix = substr($suffix, 0, $pos);
             }
         }
-        return $suffix;
+        return 0 === strpos($suffix,'.') ? $suffix : '.'.$suffix;
     }
 
     // 根据路由名称和参数生成URL地址