diff --git a/package.json b/package.json
index 147aa2f..26eb3f9 100644
--- a/package.json
+++ b/package.json
@@ -27,7 +27,7 @@
     "co": "^4.4.0",
     "debug": "^2.1.2",
     "koa-compose": "^4.0.0",
-    "ws": "^2.3.1"
+    "ws": "^3.3.0"
   },
   "devDependencies": {
     "eslint": "^4.6.1",