diff --git a/tests/integration/redirect/style.test.ts b/tests/integration/redirect/style.test.ts
index a3ff10a72..e862fc318 100644
--- a/tests/integration/redirect/style.test.ts
+++ b/tests/integration/redirect/style.test.ts
@@ -140,3 +140,37 @@ test('3. style.path: false, style.extension: false', async () => {
     'const index_module_cjs_namespaceObject = require("@/module/index.module.cjs");',
   );
 });
+
+test('should external 3rd packages CSS', async () => {
+  const { content: cssIndexJs } = queryContent(
+    contents.esm0!,
+    /esm\/less\/index\.js/,
+  );
+  const { content: cssIndexCjs } = queryContent(
+    contents.cjs0!,
+    /cjs\/less\/index\.cjs/,
+  );
+  expect(cssIndexJs).toMatchInlineSnapshot(`
+    "import "./index.css";
+    "
+  `);
+  expect(cssIndexCjs).toContain('require("./index.css");');
+
+  const { content: pkgIndexJs } = queryContent(
+    contents.esm0!,
+    /esm\/pkg\/index\.js/,
+  );
+  const { content: pkgIndexCjs } = queryContent(
+    contents.cjs0!,
+    /cjs\/pkg\/index\.cjs/,
+  );
+  expect(pkgIndexJs).toMatchInlineSnapshot(`
+    "import "element-ui/lib/theme-chunk/index.css";
+    import "element-ui/lib/theme-chunk/index";
+    "
+  `);
+  expect(pkgIndexCjs).toContain(
+    `require("element-ui/lib/theme-chunk/index.css");
+require("element-ui/lib/theme-chunk/index");`,
+  );
+});
diff --git a/tests/integration/redirect/style/rslib.config.ts b/tests/integration/redirect/style/rslib.config.ts
index add9e9721..49949c7ef 100644
--- a/tests/integration/redirect/style/rslib.config.ts
+++ b/tests/integration/redirect/style/rslib.config.ts
@@ -10,11 +10,6 @@ export default defineConfig({
     // style.extension: true
     generateBundleEsmConfig({
       bundle: false,
-      source: {
-        entry: {
-          index: ['./src/**'],
-        },
-      },
       output: {
         distPath: {
           root: 'dist/default/esm',
@@ -23,11 +18,6 @@ export default defineConfig({
     }),
     generateBundleCjsConfig({
       bundle: false,
-      source: {
-        entry: {
-          index: ['./src/**'],
-        },
-      },
       output: {
         distPath: {
           root: 'dist/default/cjs',
@@ -38,11 +28,6 @@ export default defineConfig({
     // 1. style.path: false
     generateBundleEsmConfig({
       bundle: false,
-      source: {
-        entry: {
-          index: ['./src/**'],
-        },
-      },
       redirect: {
         style: {
           path: false,
@@ -56,11 +41,6 @@ export default defineConfig({
     }),
     generateBundleCjsConfig({
       bundle: false,
-      source: {
-        entry: {
-          index: ['./src/**'],
-        },
-      },
       redirect: {
         style: {
           path: false,
diff --git a/tests/integration/redirect/style/src/pkg/index.ts b/tests/integration/redirect/style/src/pkg/index.ts
new file mode 100644
index 000000000..d77d1ce69
--- /dev/null
+++ b/tests/integration/redirect/style/src/pkg/index.ts
@@ -0,0 +1,3 @@
+// https://github.com/web-infra-dev/rslib/issues/617
+import 'element-ui/lib/theme-chunk/index.css';
+import 'element-ui/lib/theme-chunk/index';