diff --git a/components/button/button.tsx b/components/button/button.tsx
index 70c81c3fe..4be879bab 100644
--- a/components/button/button.tsx
+++ b/components/button/button.tsx
@@ -1,8 +1,9 @@
 import React from 'react';
 import PropTypes from 'prop-types';
 import classNames from 'classnames';
-import Icon from '../icon';
 import omit from 'omit.js';
+import Icon from '../icon';
+import Group from './button-group';
 
 const rxTwoCNChar = /^[\u4e00-\u9fa5]{2}$/;
 const isTwoCNChar = rxTwoCNChar.test.bind(rxTwoCNChar);
@@ -44,6 +45,7 @@ export interface ButtonProps {
   size?: ButtonSize;
   onClick?: React.FormEventHandler<any>;
   onMouseUp?: React.FormEventHandler<any>;
+  onMouseDown?: React.FormEventHandler<any>;
   loading?: boolean | { delay?: number };
   disabled?: boolean;
   style?: React.CSSProperties;
@@ -53,7 +55,7 @@ export interface ButtonProps {
 }
 
 export default class Button extends React.Component<ButtonProps, any> {
-  static Group: any;
+  static Group: typeof Group;
   static __ANT_BUTTON = true;
 
   static defaultProps = {
diff --git a/components/radio/radio.tsx b/components/radio/radio.tsx
index c369f7cfa..75d38f72a 100644
--- a/components/radio/radio.tsx
+++ b/components/radio/radio.tsx
@@ -7,7 +7,7 @@ import { AbstractCheckboxProps } from '../checkbox/Checkbox';
 import RadioGroup from './group';
 import RadioButton from './radioButton';
 
-export interface RadioProps extends AbstractCheckboxProps {}
+export type RadioProps = AbstractCheckboxProps;
 
 export default class Radio extends React.Component<RadioProps, any> {
   static Group: typeof RadioGroup;
diff --git a/components/radio/radioButton.tsx b/components/radio/radioButton.tsx
index f2b95c46c..548c12909 100644
--- a/components/radio/radioButton.tsx
+++ b/components/radio/radioButton.tsx
@@ -3,7 +3,7 @@ import PropTypes from 'prop-types';
 import { AbstractCheckboxProps } from '../checkbox/Checkbox';
 import Radio from './radio';
 
-export interface RadioButtonProps extends AbstractCheckboxProps {}
+export type RadioButtonProps = AbstractCheckboxProps;
 
 export default class RadioButton extends React.Component<RadioButtonProps, any> {
   static defaultProps = {