diff --git a/package.json b/package.json
index cf8bc7af..9b78e048 100644
--- a/package.json
+++ b/package.json
@@ -58,6 +58,7 @@
     "consola": "^3.4.0",
     "debug": "^4.4.0",
     "esbuild": "^0.25.0",
+    "fix-dts-default-cjs-exports": "^1.0.0",
     "joycon": "^3.1.1",
     "picocolors": "^1.1.1",
     "postcss-load-config": "^6.0.1",
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 55c69cf8..73a76744 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -26,6 +26,9 @@ importers:
       esbuild:
         specifier: ^0.25.0
         version: 0.25.0
+      fix-dts-default-cjs-exports:
+        specifier: ^1.0.0
+        version: 1.0.0
       joycon:
         specifier: ^3.1.1
         version: 3.1.1
@@ -1074,6 +1077,9 @@ packages:
     resolution: {integrity: sha512-YsGpe3WHLK8ZYi4tWDg2Jy3ebRz2rXowDxnld4bkQB00cc/1Zw9AWnC0i9ztDJitivtQvaI9KaLyKrc+hBW0yg==}
     engines: {node: '>=8'}
 
+  fix-dts-default-cjs-exports@1.0.0:
+    resolution: {integrity: sha512-i9Vd++WOWo6JilNgZvNvmy1T0r+/j7vikghQSEhKIuDwz4GjUrYj+Z18zlL7MleYNxE+xE6t3aG7LiAwA1P+dg==}
+
   flat@6.0.1:
     resolution: {integrity: sha512-/3FfIa8mbrg3xE7+wAhWeV+bd7L2Mof+xtZb5dRDKZ+wDvYJK4WDYeIOuOhre5Yv5aQObZrlbRmk3RTSiuQBtw==}
     engines: {node: '>=18'}
@@ -2533,6 +2539,12 @@ snapshots:
       to-regex-range: 5.0.1
     optional: true
 
+  fix-dts-default-cjs-exports@1.0.0:
+    dependencies:
+      magic-string: 0.30.17
+      mlly: 1.7.4
+      rollup: 4.34.8
+
   flat@6.0.1: {}
 
   foreground-child@3.3.0:
diff --git a/src/rollup.ts b/src/rollup.ts
index 37fe2358..b13ac569 100644
--- a/src/rollup.ts
+++ b/src/rollup.ts
@@ -11,6 +11,7 @@ import { getProductionDeps, loadPkg } from './load'
 import { reportSize } from './lib/report-size'
 import type { NormalizedOptions } from './'
 import type { InputOptions, OutputOptions, Plugin } from 'rollup'
+import { FixDtsDefaultCjsExportsPlugin } from 'fix-dts-default-cjs-exports/rollup'
 
 const logger = createLogger()
 
@@ -89,25 +90,6 @@ const getRollupConfig = async (
     },
   }
 
-  const fixCjsExport: Plugin = {
-    name: 'tsup:fix-cjs-export',
-    renderChunk(code, info) {
-      if (
-        info.type !== 'chunk' ||
-        !/\.(ts|cts)$/.test(info.fileName) ||
-        !info.isEntry ||
-        info.exports?.length !== 1 ||
-        info.exports[0] !== 'default'
-      )
-        return
-
-      return code.replace(
-        /(?<=(?<=[;}]|^)\s*export\s*){\s*([\w$]+)\s*as\s+default\s*}/,
-        `= $1`,
-      )
-    },
-  }
-
   return {
     inputConfig: {
       input: dtsOptions.entry,
@@ -167,7 +149,7 @@ const getRollupConfig = async (
         entryFileNames: `[name]${outputExtension}`,
         chunkFileNames: `[name]-[hash]${outputExtension}`,
         plugins: [
-          format === 'cjs' && options.cjsInterop && fixCjsExport,
+          format === 'cjs' && options.cjsInterop && FixDtsDefaultCjsExportsPlugin(),
         ].filter(Boolean),
       }
     }),