diff --git a/types/postcss-less/index.d.ts b/types/postcss-less/index.d.ts
index 9bd62537fcf7ac2..892957186ad8ff9 100644
--- a/types/postcss-less/index.d.ts
+++ b/types/postcss-less/index.d.ts
@@ -10,7 +10,7 @@ import * as postcss from 'postcss';
 export = postcssLess;
 
 declare const postcssLess: postcss.Syntax & {
-    parse: postcss.Parser;
+    parse: postcss.Parser<postcss.Root>;
     stringify: postcss.Stringifier;
     nodeToString: (node: postcss.Node) => string;
 };