diff --git a/lib/servers/SockJSServer.js b/lib/servers/SockJSServer.js
index 5952886ef5..dcadf52c00 100644
--- a/lib/servers/SockJSServer.js
+++ b/lib/servers/SockJSServer.js
@@ -41,9 +41,28 @@ module.exports = class SockJSServer extends BaseServer {
   constructor(server) {
     super(server);
 
+    const webSocketServerOptions =
+      /** @type {NonNullable<WebSocketServerConfiguration["options"]>} */
+      (
+        /** @type {WebSocketServerConfiguration} */
+        (this.server.options.webSocketServer).options
+      );
+
+    /**
+     * @param {NonNullable<WebSocketServerConfiguration["options"]>} options
+     * @returns {string}
+     */
+    const getSockjsUrl = (options) => {
+      if (typeof options.sockjsUrl !== "undefined") {
+        return options.sockjsUrl;
+      }
+
+      return "/__webpack_dev_server__/sockjs.bundle.js";
+    };
+
     this.implementation = sockjs.createServer({
       // Use provided up-to-date sockjs-client
-      sockjs_url: "/__webpack_dev_server__/sockjs.bundle.js",
+      sockjs_url: getSockjsUrl(webSocketServerOptions),
       // Default logger is very annoy. Limit useless logs.
       /**
        * @param {string} severity
@@ -73,15 +92,8 @@ module.exports = class SockJSServer extends BaseServer {
     };
 
     const options = {
-      .../** @type {WebSocketServerConfiguration} */
-      (this.server.options.webSocketServer).options,
-      prefix: getPrefix(
-        /** @type {NonNullable<WebSocketServerConfiguration["options"]>} */
-        (
-          /** @type {WebSocketServerConfiguration} */
-          (this.server.options.webSocketServer).options
-        )
-      ),
+      ...webSocketServerOptions,
+      prefix: getPrefix(webSocketServerOptions),
     };
 
     this.implementation.installHandlers(