diff --git a/packages/vant/src/number-keyboard/README.md b/packages/vant/src/number-keyboard/README.md
index 954da5e6c..1a8c46589 100644
--- a/packages/vant/src/number-keyboard/README.md
+++ b/packages/vant/src/number-keyboard/README.md
@@ -109,6 +109,7 @@ Use `title` prop to set keyboard title.
 </van-cell>
 <van-number-keyboard
   :show="show"
+  theme="custom"
   :extra-key="['00', '.']"
   close-button-text="Close"
   @blur="show = false"
diff --git a/packages/vant/src/number-keyboard/README.zh-CN.md b/packages/vant/src/number-keyboard/README.zh-CN.md
index 6032f95a6..730ab4514 100644
--- a/packages/vant/src/number-keyboard/README.zh-CN.md
+++ b/packages/vant/src/number-keyboard/README.zh-CN.md
@@ -116,6 +116,7 @@ export default {
 </van-cell>
 <van-number-keyboard
   :show="show"
+  theme="custom"
   :extra-key="['00', '.']"
   close-button-text="完成"
   @blur="show = false"