diff --git a/lib/core/src/server/preview/iframe-webpack.config.js b/lib/core/src/server/preview/iframe-webpack.config.js
index 3cb4ac5e0fdb..02e094d195d2 100644
--- a/lib/core/src/server/preview/iframe-webpack.config.js
+++ b/lib/core/src/server/preview/iframe-webpack.config.js
@@ -37,7 +37,7 @@ export default ({
     devtool: '#cheap-module-source-map',
     entry: entries,
     output: {
-      path: path.join(process.cwd(), outputDir),
+      path: path.resolve(process.cwd(), outputDir),
       filename: '[name].[hash].bundle.js',
       publicPath: '',
     },