diff --git a/frontend/src/App.tsx b/frontend/src/App.tsx
index 8b97f1c9..1e7dad52 100644
--- a/frontend/src/App.tsx
+++ b/frontend/src/App.tsx
@@ -31,6 +31,7 @@ import { GitHubLoginDialog } from '@/components/GitHubLoginDialog';
 import { ReleaseNotesDialog } from '@/components/ReleaseNotesDialog';
 import { AppWithStyleOverride } from '@/utils/style-override';
 import { WebviewContextMenu } from '@/vscode/ContextMenu';
+import { DevBanner } from '@/components/DevBanner';
 
 const SentryRoutes = Sentry.withSentryReactRouterV6Routing(Routes);
 
@@ -212,6 +213,7 @@ function AppContent() {
             />
             <CreatePRDialog />
             <TaskFormDialogContainer />
+            {showNavbar && <DevBanner />}
             {showNavbar && <Navbar />}
             <div className="flex-1 h-full overflow-y-scroll">
               <SentryRoutes>
diff --git a/frontend/src/components/DevBanner.tsx b/frontend/src/components/DevBanner.tsx
new file mode 100644
index 00000000..b6e13607
--- /dev/null
+++ b/frontend/src/components/DevBanner.tsx
@@ -0,0 +1,17 @@
+import { AlertTriangle } from 'lucide-react';
+
+export function DevBanner() {
+  // Only show in development mode
+  if (import.meta.env.MODE !== 'development') {
+    return null;
+  }
+
+  return (
+    <div className="bg-orange-500 text-white text-center py-2 px-4 text-sm font-medium border-b border-orange-600">
+      <div className="flex items-center justify-center gap-2">
+        <AlertTriangle className="h-4 w-4" />
+        <span>Development Mode - This is a development build</span>
+      </div>
+    </div>
+  );
+}