diff --git a/style/components/menu.less b/style/components/menu.less
index 10e98f23d8..fe17ab7b4f 100644
--- a/style/components/menu.less
+++ b/style/components/menu.less
@@ -5,7 +5,7 @@
   margin-bottom: 0;
   padding-left: 0; // Override default ul/ol
   list-style: none;
-  z-index: 1001;
+  z-index: 999;
   border: 1px solid #d9d9d9;
   box-shadow: @overlay-shadow;
   border-radius: @border-radius-base;