diff --git a/packages/material-ui/src/Hidden/HiddenCss.d.ts b/packages/material-ui/src/Hidden/HiddenCss.d.ts
index 49070c4c9eafcc..7d4c12c62653ef 100644
--- a/packages/material-ui/src/Hidden/HiddenCss.d.ts
+++ b/packages/material-ui/src/Hidden/HiddenCss.d.ts
@@ -2,6 +2,7 @@ import * as React from 'react';
 import { Breakpoint } from '../styles/createBreakpoints';
 
 export interface HiddenCssProps {
+  className?: string;
   lgDown?: boolean;
   lgUp?: boolean;
   mdDown?: boolean;