diff --git a/components/datepicker/demo/size.md b/components/datepicker/demo/size.md
new file mode 100644
index 0000000000..c867dbcfbd
--- /dev/null
+++ b/components/datepicker/demo/size.md
@@ -0,0 +1,20 @@
+# 三种大小
+
+- order: 1
+
+三种大小的输入框，`size`为`lg`和`sm`分别表示高为`32px`和`22px`，默认`28px`。
+
+---
+
+````jsx
+// or require('antd/lib/datepicker');
+var Datepicker = antd.Datepicker;
+
+React.render(
+  <div>
+    <Datepicker size="sm" value="" />
+    <Datepicker value="" />
+    <Datepicker size="lg" value="" />
+  </div>
+, document.getElementById('components-datepicker-demo-size'));
+````
diff --git a/components/datepicker/index.jsx b/components/datepicker/index.jsx
index a4fae950f6..062842b021 100644
--- a/components/datepicker/index.jsx
+++ b/components/datepicker/index.jsx
@@ -74,7 +74,7 @@ export default React.createClass({
         value={this.state.value}
         prefixCls="ant-calendar-picker"
         onChange={this.handleChange}>
-        <input placeholder={this.props.placeholder} className="ant-calendar-picker-input ant-input" />
+        <input placeholder={this.props.placeholder} className={'ant-calendar-picker-input ant-input ant-input-' + this.props.size}/>
       </Datepicker>
     );
   }
diff --git a/components/datepicker/index.md b/components/datepicker/index.md
index afa0e26365..5f8f4578be 100644
--- a/components/datepicker/index.md
+++ b/components/datepicker/index.md
@@ -26,6 +26,7 @@
 | onSelect     | 选择日期的回调 | function | 无           |
 | showTime     | 显示时间选择条 | boolean  | false        |
 | disabled     | 禁用           | bool     | false        |
+| size         | 输入框大小，`lg`代表高为32px，`sm`代表高为22px，默认28px      | string   | 无        |
 
 <style>
 .code-box-demo .ant-calendar-picker-input {