diff --git a/lib/loader.js b/lib/loader.js
index f43e005e..24527736 100644
--- a/lib/loader.js
+++ b/lib/loader.js
@@ -91,6 +91,7 @@ module.exports = function(content, map) {
 		var moduleJs;
 		if(query.sourceMap && result.map) {
 			// add a SourceMap
+			var suffixRE = /\.[^.\/\\]*$/; // replace suffix to css for .sass or .less files
 			map = result.map;
 			if(map.sources) {
 				map.sources = map.sources.map(function(source) {
@@ -98,11 +99,11 @@ module.exports = function(content, map) {
 					var p = path.relative(query.context || this.options.context, source).replace(/\\/g, "/");
 					if(p.indexOf("../") !== 0)
 						p = "./" + p;
-					return "/" + p;
+					return "/" + p.replace(suffixRE,'.css');
 				}, this);
 				map.sourceRoot = "webpack://";
 			}
-			map.file = map.file.split("!").pop();
+			map.file = map.file.split("!").pop().replace(suffixRE,'.css');
 			map = JSON.stringify(map);
 			moduleJs = "exports.push([module.id, " + cssAsString + ", \"\", " + map + "]);";
 		} else {
diff --git a/test/sourceMapTest.js b/test/sourceMapTest.js
index 9c29729a..c4660318 100644
--- a/test/sourceMapTest.js
+++ b/test/sourceMapTest.js
@@ -52,11 +52,11 @@ describe("source maps", function() {
 		query: "?sourceMap"
 	}, [
 		[1, ".class { a: b c d; }", "", {
-			file: 'test.scss',
+			file: 'test.css',
 			mappings: 'AAAA,SAAS,SAAS,EAAE',
 			names: [],
 			sourceRoot: 'webpack://',
-			sources: [ '/./folder/test.scss' ],
+			sources: [ '/./folder/test.css' ],
 			sourcesContent: [ '.class { a: b c d; }' ],
 			version: 3
 		}]