diff --git a/appengine/websockets/package.json b/appengine/websockets/package.json
index 67e2224561..1adf6c23b5 100644
--- a/appengine/websockets/package.json
+++ b/appengine/websockets/package.json
@@ -19,7 +19,7 @@
   "dependencies": {
     "express": "^4.15.4",
     "pug": "^2.0.3",
-    "socket.io": "^2.2.0"
+    "socket.io": "^3.0.0"
   },
   "devDependencies": {
     "@google-cloud/nodejs-repo-tools": "^3.3.0",