diff --git a/components/button/index.zh-CN.md b/components/button/index.zh-CN.md
index 2ef9d4d61d..040001a026 100644
--- a/components/button/index.zh-CN.md
+++ b/components/button/index.zh-CN.md
@@ -44,7 +44,7 @@ cover: https://gw.alipayobjects.com/zos/alicdn/fNUKzY1sk/Button.svg
 | icon | 设置按钮的图标组件 | ReactNode | - |  |
 | loading | 设置按钮载入状态 | boolean \| { delay: number } | false |  |
 | shape | 设置按钮形状 | `circle` \| `round` | - |  |
-| size | 设置按钮大小 | `large` \| `middle` \| `small` | - |  |
+| size | 设置按钮大小 | `large` \| `middle` \| `small` | `middle` |  |
 | target | 相当于 a 链接的 target 属性，href 存在时生效 | string | - |  |
 | type | 设置按钮类型 | `primary` \| `ghost` \| `dashed` \| `link` \| `text` \| `default` | `default` |  |
 | onClick | 点击按钮时的回调 | (event) => void | - |  |