diff --git a/lib/dev.js b/lib/dev.js
index 784f7ea..5966743 100644
--- a/lib/dev.js
+++ b/lib/dev.js
@@ -14,7 +14,7 @@ const SERVER_OPTIONS = {}
 
 export default function createServer(root = '', conf = {}) {
   const IS_MPA = Object.keys(conf.pages).length > 1
-  const PORT = conf.devServer.port
+  const PORT = conf.devServer.port || 8080
   const USE_HTTPS = conf.devServer.https
   const DOMAIN = conf.devServer.domain || 'localhost'
   const WEB_SERVER = USE_HTTPS ? https : http
@@ -175,7 +175,7 @@ export default function createServer(root = '', conf = {}) {
     .listen(PORT)
     .on('error', err => {
       console.log(`${PORT}端口被占用~~~`)
-      conf.devServer.port++
+      conf.devServer.port = PORT + 1
       createServer(root, conf)
     })
     .on('listening', _ => {