diff --git a/lib/serve.js b/lib/serve.js
index acde5a7..b155604 100644
--- a/lib/serve.js
+++ b/lib/serve.js
@@ -62,7 +62,6 @@ function serve(staticPath, options) {
   const opts = Object.assign({
     etag: true,
     lastModified: true,
-    extname: ['.html', '.htm'],
   }, options);
   debug('static path:%s, opts:%j', staticPath, opts);
   if (options && (options.disableETag || options.disableLastModified)) {
diff --git a/package.json b/package.json
index 9d3cacc..84c81f1 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "koa-static-serve",
   "description": "static serve middlware for koa",
-  "version": "2.1.1",
+  "version": "2.1.2",
   "author": "Tree Xie <vicansocanbico@gmail.com>",
   "keywords": [
     "koa",
diff --git a/test/serve.js b/test/serve.js
index 2bcbcf5..3740ad7 100644
--- a/test/serve.js
+++ b/test/serve.js
@@ -63,7 +63,9 @@ describe('serve', function() {
   it('should add default ext successful', done => {
     const app = new Koa();
 
-    app.use(serve(assets));
+    app.use(serve(assets, {
+      extname: ['.html'],
+    }));
     request(app.listen())
       .get('/index')
       .expect(200, done);