diff --git a/apps/ssr/api/index.ts b/apps/ssr/api/index.ts
index eaf5e8d32..81454085f 100644
--- a/apps/ssr/api/index.ts
+++ b/apps/ssr/api/index.ts
@@ -1,6 +1,6 @@
 // @ts-ignore
 // eslint-disable-next-line antfu/no-import-dist
-import { createApp } from "../dist/server/index.js"
+import { createApp } from "../dist/server/index.mjs"
 
 export default async function handler(req: any, res: any) {
   const app = await createApp()
diff --git a/apps/ssr/tsdown.config.ts b/apps/ssr/tsdown.config.ts
index 7d4d6364f..5697d2126 100644
--- a/apps/ssr/tsdown.config.ts
+++ b/apps/ssr/tsdown.config.ts
@@ -21,7 +21,7 @@ export default defineConfig({
     hooks.hook("build:done", async () => {
       if (process.env.VERCEL !== "1") return
 
-      const outputFile = "dist/server/index.js"
+      const outputFile = "dist/server/index.mjs"
       const tempFile = `${outputFile}.tmp`
 
       try {