diff --git a/apps/ui/src/main.ts b/apps/ui/src/main.ts
index 4e112f25..b2f7bd86 100644
--- a/apps/ui/src/main.ts
+++ b/apps/ui/src/main.ts
@@ -6,7 +6,7 @@
  */
 
 import path from 'path';
-import { spawn, ChildProcess } from 'child_process';
+import { spawn, execSync, ChildProcess } from 'child_process';
 import fs from 'fs';
 import crypto from 'crypto';
 import http, { Server } from 'http';
@@ -595,9 +595,20 @@ app.on('window-all-closed', () => {
 });
 
 app.on('before-quit', () => {
-  if (serverProcess) {
+  if (serverProcess && serverProcess.pid) {
     console.log('[Electron] Stopping server...');
-    serverProcess.kill();
+    if (process.platform === 'win32') {
+      try {
+        // Windows: use taskkill with /t to kill entire process tree
+        // This prevents orphaned node processes when closing the app
+        // Using execSync to ensure process is killed before app exits
+        execSync(`taskkill /f /t /pid ${serverProcess.pid}`, { stdio: 'ignore' });
+      } catch (error) {
+        console.error('[Electron] Failed to kill server process:', (error as Error).message);
+      }
+    } else {
+      serverProcess.kill('SIGTERM');
+    }
     serverProcess = null;
   }