diff --git a/src/components/menu/submenu.vue b/src/components/menu/submenu.vue
index 216d1b1..9f78244 100644
--- a/src/components/menu/submenu.vue
+++ b/src/components/menu/submenu.vue
@@ -12,7 +12,7 @@
                 v-show="opened"
                 placement="bottom"
                 ref="drop"
-                :style="dropStyle"><ul><slot></slot></ul>
+                :style="dropStyle"><ul :class="[prefixCls + '-drop-list']"><slot></slot></ul>
             </Drop>
         </transition>
     </li>
--
libgit2 0.21.4