diff --git a/lib/loader.js b/lib/loader.js
index ea4d8372a..d4486d0ab 100644
--- a/lib/loader.js
+++ b/lib/loader.js
@@ -22,6 +22,13 @@ module.exports = function(content, map) {
 	if(sourceMap) {
 		if (map && typeof map !== "string") {
 			map = JSON.stringify(map);
+
+			if (map.sources) {
+				map.sources = map.sources.map(function (source) {
+					return source.replace(/\\/g, '/');
+				});
+				map.sourceRoot = '';
+			}
 		}
 	} else {
 		// Some loaders (example `"postcss-loader": "1.x.x"`) always generates source map, we should remove it
@@ -30,8 +37,8 @@ module.exports = function(content, map) {
 
 	processCss(content, map, {
 		mode: moduleMode ? "local" : "global",
-		from: loaderUtils.getRemainingRequest(this),
-		to: loaderUtils.getCurrentRequest(this),
+		from: loaderUtils.getRemainingRequest(this).split("!").pop(),
+		to: loaderUtils.getCurrentRequest(this).split("!").pop(),
 		query: query,
 		minimize: this.minimize,
 		loaderContext: this,
@@ -105,11 +112,11 @@ module.exports = function(content, map) {
 			map = result.map;
 			if(map.sources) {
 				map.sources = map.sources.map(function(source) {
-					return source.split("!").pop();
+					return source.split("!").pop().replace(/\\/g, '/');
 				}, this);
 				map.sourceRoot = "";
 			}
-			map.file = map.file.split("!").pop();
+			map.file = map.file.split("!").pop().replace(/\\/g, '/');
 			map = JSON.stringify(map);
 			moduleJs = "exports.push([module.id, " + cssAsString + ", \"\", " + map + "]);";
 		} else {
diff --git a/test/sourceMapTest.js b/test/sourceMapTest.js
index 3bb84f660..d48578675 100644
--- a/test/sourceMapTest.js
+++ b/test/sourceMapTest.js
@@ -10,24 +10,50 @@ describe("source maps", function() {
 	testWithMap("falsy: undefined map doesn't cause an error", ".class { a: b c d; }", undefined, [
 		[1, ".class { a: b c d; }", ""]
 	]);
-    testWithMap("should don't generate sourceMap when `sourceMap: false` and map exist",
+	testWithMap("should don't generate sourceMap when `sourceMap: false` and map exist",
 		".class { a: b c d; }",
-        {
-            file: 'test.css',
-            mappings: 'AAAA,SAAS,SAAS,EAAE',
-            names: [],
-            sourceRoot: '',
-            sources: [ '/folder/test.css' ],
-            sourcesContent: [ '.class { a: b c d; }' ],
-            version: 3
-        },
+		{
+			file: 'test.css',
+			mappings: 'AAAA,SAAS,SAAS,EAAE',
+			names: [],
+			sourceRoot: '',
+			sources: [ '/folder/test.css' ],
+			sourcesContent: [ '.class { a: b c d; }' ],
+			version: 3
+		},
 		[
 			[1, ".class { a: b c d; }", ""]
 		],
-		{
-            query: "?sourceMap=false"
-		}
+        {
+            sourceMap: false
+        }
 	);
+    testWithMap("generate sourceMap when `sourceMap: true` and map exist",
+        ".class { a: b c d; }",
+        {
+            file: "test.css",
+            mappings: "AAAA,SAAS,SAAS,EAAE",
+            names: [],
+            sourceRoot: "",
+            sources: [ "/folder/test.css" ],
+            sourcesContent: [ ".class { a: b c d; }" ],
+            version: 3
+        },
+        [
+            [1, ".class { a: b c d; }", "", {
+                file: "test.css",
+                mappings: "AAAA,SAAS,SAAS,EAAE",
+                names: [],
+                sourceRoot: "",
+                sources: [ "/folder/test.css" ],
+                sourcesContent: [ ".class { a: b c d; }" ],
+                version: 3
+            }]
+        ],
+        {
+            sourceMap: true
+        }
+    );
 	testMap("generate sourceMap (1 loader)", ".class { a: b c d; }", undefined, {
 		loaders: [{request: "/path/css-loader"}],
 		options: { context: "/" },
@@ -45,6 +71,23 @@ describe("source maps", function() {
 			version: 3
 		}]
 	]);
+	testMap("generate sourceMap (1 loader) with backslash (windows)", ".class { a: b c d; }", undefined, {
+		loaders: [{request: "C:\\path\\css-loader"}],
+		options: { context: "\\" },
+		resource: "C:\\folder\\test.css",
+		request: "C:\\path\\css-loader!C:\\folder\\test.css",
+		query: "?sourceMap"
+	}, [
+		[1, ".class { a: b c d; }", "", {
+			file: 'C:/folder/test.css',
+			mappings: 'AAAA,SAAS,SAAS,EAAE',
+			names: [],
+			sourceRoot: '',
+			sources: [ 'C:/folder/test.css' ],
+			sourcesContent: [ '.class { a: b c d; }' ],
+			version: 3
+		}]
+	]);
 	testMap("generate sourceMap (1 loader, relative)", ".class { a: b c d; }", undefined, {
 		loaders: [{request: "/path/css-loader"}],
 		options: { context: "/other-folder/sub" },
@@ -113,6 +156,23 @@ describe("source maps", function() {
 			version: 3
 		}]
 	]);
+	testMap("generate sourceMap (2 loaders) with backslash (windows)", ".class { a: b c d; }", undefined, {
+		loaders: [{request: "C:\\path\\css-loader"}, {request: "C:\\path\\sass-loader"}],
+		options: { context: "\\" },
+		resource: "C:\\folder\\test.scss",
+		request: "C:\\path\\css-loader!C:\\path\\sass-loader!C:\\folder\\test.scss",
+		query: "?sourceMap"
+	}, [
+		[1, ".class { a: b c d; }", "", {
+			file: 'C:/folder/test.scss',
+			mappings: 'AAAA,SAAS,SAAS,EAAE',
+			names: [],
+			sourceRoot: '',
+			sources: [ 'C:/folder/test.scss' ],
+			sourcesContent: [ '.class { a: b c d; }' ],
+			version: 3
+		}]
+	]);
 	testMap("don't generate sourceMap (1 loader)", ".class { a: b c d; }", undefined, {
 		loaders: [{request: "/path/css-loader"}],
 		options: { context: "/" },