diff --git a/e2e/cases/dts/__snapshots__/index.test.ts.snap b/e2e/cases/dts/__snapshots__/index.test.ts.snap
index 099f93cc9..4bce88be6 100644
--- a/e2e/cases/dts/__snapshots__/index.test.ts.snap
+++ b/e2e/cases/dts/__snapshots__/index.test.ts.snap
@@ -1,6 +1,6 @@
 // Vitest Snapshot v1, https://vitest.dev/guide/snapshot.html
 
-exports[`dts when bundle: false > basic 1`] = `
+exports[`dts when bundle: false > basic 2`] = `
 {
   "./dist/esm/index.d.ts": "export * from './utils/numbers';
 export * from './utils/strings';
diff --git a/e2e/cases/dts/bundle-false/autoExtension.config.ts b/e2e/cases/dts/bundle-false/autoExtension.config.ts
new file mode 100644
index 000000000..39499785f
--- /dev/null
+++ b/e2e/cases/dts/bundle-false/autoExtension.config.ts
@@ -0,0 +1,21 @@
+import { generateBundleCjsConfig, generateBundleEsmConfig } from '@e2e/helper';
+import { defineConfig } from '@rslib/core';
+
+export default defineConfig({
+  lib: [
+    generateBundleEsmConfig(__dirname, {
+      bundle: false,
+    }),
+    generateBundleCjsConfig(__dirname, {
+      bundle: false,
+      dts: {
+        bundle: false,
+      },
+    }),
+  ],
+  source: {
+    entry: {
+      main: ['./src/**'],
+    },
+  },
+});
diff --git a/e2e/cases/dts/bundle-false/package.json b/e2e/cases/dts/bundle-false/package.json
new file mode 100644
index 000000000..aa0ce962e
--- /dev/null
+++ b/e2e/cases/dts/bundle-false/package.json
@@ -0,0 +1,6 @@
+{
+  "name": "dts-bundle-false-test",
+  "version": "1.0.0",
+  "private": true,
+  "type": "module"
+}
diff --git a/e2e/cases/dts/bundle/autoExtension.config.ts b/e2e/cases/dts/bundle/autoExtension.config.ts
new file mode 100644
index 000000000..c58dcca06
--- /dev/null
+++ b/e2e/cases/dts/bundle/autoExtension.config.ts
@@ -0,0 +1,18 @@
+import { generateBundleCjsConfig, generateBundleEsmConfig } from '@e2e/helper';
+import { defineConfig } from '@rslib/core';
+
+export default defineConfig({
+  lib: [
+    generateBundleEsmConfig(__dirname),
+    generateBundleCjsConfig(__dirname, {
+      dts: {
+        bundle: true,
+      },
+    }),
+  ],
+  source: {
+    entry: {
+      main: './src/index.ts',
+    },
+  },
+});
diff --git a/e2e/cases/dts/index.test.ts b/e2e/cases/dts/index.test.ts
index 7c7cad48b..08a8f5ae2 100644
--- a/e2e/cases/dts/index.test.ts
+++ b/e2e/cases/dts/index.test.ts
@@ -11,8 +11,14 @@ describe('dts when bundle: false', () => {
       'dts',
     );
 
-    expect(files.esm?.length).toBe(4);
-    expect(files.esm?.[0]!.endsWith('.d.ts')).toEqual(true);
+    expect(files.esm).toMatchInlineSnapshot(`
+      [
+        "./dist/esm/index.d.ts",
+        "./dist/esm/sum.d.ts",
+        "./dist/esm/utils/numbers.d.ts",
+        "./dist/esm/utils/strings.d.ts",
+      ]
+    `);
     expect(contents.esm).toMatchSnapshot();
   });
 
@@ -34,8 +40,15 @@ describe('dts when bundle: false', () => {
       'distPath.config.ts',
       'dts',
     );
-    expect(files.esm?.length).toBe(4);
-    expect(files.esm?.[0]!.startsWith('./dist/custom')).toEqual(true);
+
+    expect(files.esm).toMatchInlineSnapshot(`
+      [
+        "./dist/custom/index.d.ts",
+        "./dist/custom/sum.d.ts",
+        "./dist/custom/utils/numbers.d.ts",
+        "./dist/custom/utils/strings.d.ts",
+      ]
+    `);
   });
 
   test('abortOnError: false', async () => {
@@ -48,6 +61,24 @@ describe('dts when bundle: false', () => {
 
     expect(isSuccess).toBe(true);
   });
+
+  test('autoExtension: true', async () => {
+    const fixturePath = join(__dirname, 'bundle-false');
+    const { files } = await buildAndGetResults(
+      fixturePath,
+      'autoExtension.config.ts',
+      'dts',
+    );
+
+    expect(files.cjs).toMatchInlineSnapshot(`
+      [
+        "./dist/cjs/index.d.cts",
+        "./dist/cjs/sum.d.cts",
+        "./dist/cjs/utils/numbers.d.cts",
+        "./dist/cjs/utils/strings.d.cts",
+      ]
+    `);
+  });
 });
 
 describe('dts when bundle: true', () => {
@@ -59,7 +90,7 @@ describe('dts when bundle: true', () => {
       'dts',
     );
 
-    expect(entryFiles.esm!.endsWith('index.d.ts')).toEqual(true);
+    expect(entryFiles.esm).toEqual('./dist/esm/index.d.ts');
     expect(entries).toMatchSnapshot();
   });
 
@@ -82,7 +113,7 @@ describe('dts when bundle: true', () => {
       'dts',
     );
 
-    expect(entryFiles.esm!.startsWith('./dist/custom')).toEqual(true);
+    expect(entryFiles.esm).toEqual('./dist/custom/index.d.ts');
   });
 
   test('abortOnError: false', async () => {
@@ -95,4 +126,15 @@ describe('dts when bundle: true', () => {
 
     expect(isSuccess).toBe(true);
   });
+
+  test('autoExtension: true', async () => {
+    const fixturePath = join(__dirname, 'bundle');
+    const { entryFiles } = await buildAndGetResults(
+      fixturePath,
+      'autoExtension.config.ts',
+      'dts',
+    );
+
+    expect(entryFiles.cjs).toEqual('./dist/cjs/index.d.cts');
+  });
 });
diff --git a/examples/express-plugin/rslib.config.ts b/examples/express-plugin/rslib.config.ts
index 3d5b07565..f4d96ea59 100644
--- a/examples/express-plugin/rslib.config.ts
+++ b/examples/express-plugin/rslib.config.ts
@@ -1,7 +1,6 @@
 import { defineConfig } from '@rslib/core';
 
 const shared = {
-  autoExtension: true,
   dts: {
     bundle: false,
   },
diff --git a/examples/react-component/rslib.config.ts b/examples/react-component/rslib.config.ts
index db1d311d7..d97011009 100644
--- a/examples/react-component/rslib.config.ts
+++ b/examples/react-component/rslib.config.ts
@@ -2,7 +2,6 @@ import { pluginReact } from '@rsbuild/plugin-react';
 import { defineConfig } from '@rslib/core';
 
 const shared = {
-  autoExtension: true,
   dts: {
     bundle: false,
   },
diff --git a/packages/core/src/config.ts b/packages/core/src/config.ts
index 6017a7410..e39f100bc 100644
--- a/packages/core/src/config.ts
+++ b/packages/core/src/config.ts
@@ -168,19 +168,25 @@ const composeAutoExtensionConfig = (
   format: Format,
   root: string,
   autoExtension: boolean,
-): RsbuildConfig => {
-  const { jsExtension } = getDefaultExtension({
+): {
+  config: RsbuildConfig;
+  dtsExtension: string;
+} => {
+  const { jsExtension, dtsExtension } = getDefaultExtension({
     format,
     root,
     autoExtension,
   });
 
   return {
-    output: {
-      filename: {
-        js: `[name]${jsExtension}`,
+    config: {
+      output: {
+        filename: {
+          js: `[name]${jsExtension}`,
+        },
       },
     },
+    dtsExtension,
   };
 };
 
@@ -325,6 +331,7 @@ const composeBundleConfig = (bundle = true): RsbuildConfig => {
 
 const composeDtsConfig = async (
   libConfig: LibConfig,
+  dtsExtension: string,
 ): Promise<RsbuildConfig> => {
   const { dts, bundle, output } = libConfig;
 
@@ -337,6 +344,7 @@ const composeDtsConfig = async (
         bundle: dts?.bundle ?? bundle,
         distPath: dts?.distPath ?? output?.distPath?.root ?? './dist',
         abortOnError: dts?.abortOnError ?? true,
+        dtsExtension,
       }),
     ],
   };
@@ -389,11 +397,8 @@ async function composeLibRsbuildConfig(
 
   const { format, autoExtension = true } = config;
   const formatConfig = composeFormatConfig(format!);
-  const autoExtensionConfig = composeAutoExtensionConfig(
-    format!,
-    dirname(configPath),
-    autoExtension,
-  );
+  const { config: autoExtensionConfig, dtsExtension } =
+    composeAutoExtensionConfig(format!, dirname(configPath), autoExtension);
   const bundleConfig = composeBundleConfig(config.bundle);
   const targetConfig = composeTargetConfig(config.output?.target);
   const syntaxConfig = composeSyntaxConfig(
@@ -405,7 +410,7 @@ async function composeLibRsbuildConfig(
     config.bundle,
     dirname(configPath),
   );
-  const dtsConfig = await composeDtsConfig(config);
+  const dtsConfig = await composeDtsConfig(config, dtsExtension);
 
   return mergeRsbuildConfig(
     formatConfig,
diff --git a/packages/plugin-dts/package.json b/packages/plugin-dts/package.json
index 7e3523e03..e7fd94536 100644
--- a/packages/plugin-dts/package.json
+++ b/packages/plugin-dts/package.json
@@ -30,6 +30,7 @@
     "dev": "modern build --watch"
   },
   "dependencies": {
+    "fast-glob": "^3.3.2",
     "picocolors": "1.0.1"
   },
   "devDependencies": {
diff --git a/packages/plugin-dts/src/apiExtractor.ts b/packages/plugin-dts/src/apiExtractor.ts
index 58a5ec4bd..a92e1a00a 100644
--- a/packages/plugin-dts/src/apiExtractor.ts
+++ b/packages/plugin-dts/src/apiExtractor.ts
@@ -5,23 +5,34 @@ import {
   type ExtractorResult,
 } from '@microsoft/api-extractor';
 import { logger } from '@rsbuild/core';
+import color from 'picocolors';
+import { getTimeCost } from './utils';
 
 export type BundleOptions = {
+  name: string;
   cwd: string;
   outDir: string;
+  dtsExtension: string;
   entry?: string;
   tsconfigPath?: string;
 };
 
-export function bundleDts(options: BundleOptions): void {
+export async function bundleDts(options: BundleOptions): Promise<void> {
   const {
+    name,
     cwd,
     outDir,
+    dtsExtension,
     entry = 'index.d.ts',
     tsconfigPath = 'tsconfig.json',
   } = options;
   try {
-    const untrimmedFilePath = join(cwd, relative(cwd, outDir), 'index.d.ts');
+    const start = Date.now();
+    const untrimmedFilePath = join(
+      cwd,
+      relative(cwd, outDir),
+      `index${dtsExtension}`,
+    );
     const internalConfig = {
       mainEntryPointFilePath: entry,
       // TODO: use !externals
@@ -49,11 +60,11 @@ export function bundleDts(options: BundleOptions): void {
     });
 
     if (!extractorResult.succeeded) {
-      throw new Error('API Extractor rollup error');
+      throw new Error(`API Extractor error. ${color.gray(`(${name})`)}`);
     }
 
     logger.info(
-      `API Extractor writing package typings succeeded: ${untrimmedFilePath}`,
+      `API Extractor bundle DTS succeeded: ${color.cyan(untrimmedFilePath)} in ${getTimeCost(start)} ${color.gray(`(${name})`)}`,
     );
   } catch (e) {
     logger.error('API Extractor', e);
diff --git a/packages/plugin-dts/src/dts.ts b/packages/plugin-dts/src/dts.ts
index aa4cb59d3..d6babe2e2 100644
--- a/packages/plugin-dts/src/dts.ts
+++ b/packages/plugin-dts/src/dts.ts
@@ -7,8 +7,16 @@ import { emitDts } from './tsc';
 import { ensureTempDeclarationDir, loadTsconfig } from './utils';
 
 export async function generateDts(data: DtsGenOptions): Promise<void> {
-  const { tsconfigPath, distPath, bundle, entryPath, cwd, isWatch, name } =
-    data;
+  const {
+    bundle,
+    distPath,
+    entryPath,
+    tsconfigPath,
+    name,
+    cwd,
+    isWatch,
+    dtsExtension = '.d.ts',
+  } = data;
   logger.start(`Generating DTS... ${color.gray(`(${name})`)}`);
   const configPath = ts.findConfigFile(cwd, ts.sys.fileExists, tsconfigPath);
   if (!configPath) {
@@ -47,11 +55,13 @@ export async function generateDts(data: DtsGenOptions): Promise<void> {
   const bundleDtsIfNeeded = async () => {
     if (bundle === true) {
       const { bundleDts } = await import('./apiExtractor');
-      bundleDts({
+      await bundleDts({
+        name,
         cwd,
         outDir,
         entry,
         tsconfigPath,
+        dtsExtension,
       });
     }
   };
@@ -62,15 +72,17 @@ export async function generateDts(data: DtsGenOptions): Promise<void> {
     }
   };
 
-  emitDts(
+  await emitDts(
     {
       name,
       cwd,
       configPath,
       rootDir,
       declarationDir,
+      dtsExtension,
     },
     onComplete,
+    bundle,
     isWatch,
   );
 
diff --git a/packages/plugin-dts/src/index.ts b/packages/plugin-dts/src/index.ts
index c9fe0fad1..648c506bd 100644
--- a/packages/plugin-dts/src/index.ts
+++ b/packages/plugin-dts/src/index.ts
@@ -6,6 +6,7 @@ export type PluginDtsOptions = {
   bundle?: boolean;
   distPath?: string;
   abortOnError?: boolean;
+  dtsExtension?: string;
 };
 
 export type DtsGenOptions = PluginDtsOptions & {
diff --git a/packages/plugin-dts/src/tsc.ts b/packages/plugin-dts/src/tsc.ts
index bc8584d10..3ee73b0fa 100644
--- a/packages/plugin-dts/src/tsc.ts
+++ b/packages/plugin-dts/src/tsc.ts
@@ -1,7 +1,12 @@
 import { logger } from '@rsbuild/core';
 import color from 'picocolors';
 import * as ts from 'typescript';
-import { getFileLoc, loadTsconfig } from './utils';
+import {
+  getFileLoc,
+  getTimeCost,
+  loadTsconfig,
+  processDtsFiles,
+} from './utils';
 
 export type emitDtsOptions = {
   name: string;
@@ -9,18 +14,17 @@ export type emitDtsOptions = {
   configPath: string;
   rootDir: string;
   declarationDir: string;
+  dtsExtension: string;
 };
 
-export function emitDts(
+export async function emitDts(
   options: emitDtsOptions,
   onComplete: (isSuccess: boolean) => void,
+  bundle = false,
   isWatch = false,
-): void {
+): Promise<void> {
   const start = Date.now();
-  const getTimeCost = () => {
-    return `${Math.floor(Date.now() - start)}ms`;
-  };
-  const { configPath, declarationDir, name } = options;
+  const { configPath, declarationDir, name, dtsExtension } = options;
   const { options: rawCompilerOptions, fileNames } = loadTsconfig(configPath);
 
   const compilerOptions = {
@@ -57,6 +61,8 @@ export function emitDts(
       diagnosticMessages.push(message);
     }
 
+    await processDtsFiles(bundle, declarationDir, dtsExtension);
+
     if (diagnosticMessages.length) {
       logger.error(
         `Failed to emit declaration files. ${color.gray(`(${name})`)}`,
@@ -70,7 +76,7 @@ export function emitDts(
     }
 
     logger.info(
-      `DTS generation succeeded in ${getTimeCost()} ${color.gray(`(${name})`)}`,
+      `DTS generation succeeded in ${getTimeCost(start)} ${color.gray(`(${name})`)}`,
     );
   } else {
     const createProgram = ts.createSemanticDiagnosticsBuilderProgram;
@@ -92,7 +98,7 @@ export function emitDts(
       );
     };
 
-    const reportWatchStatusChanged: ts.WatchStatusReporter = (
+    const reportWatchStatusChanged: ts.WatchStatusReporter = async (
       diagnostic: ts.Diagnostic,
       _newLine: string,
       _options: ts.CompilerOptions,
@@ -117,11 +123,13 @@ export function emitDts(
         } else {
           logger.error(message);
         }
+        await processDtsFiles(bundle, declarationDir, dtsExtension);
       }
 
       // 6193: 1 error
       if (diagnostic.code === 6193) {
         logger.error(message);
+        await processDtsFiles(bundle, declarationDir, dtsExtension);
       }
     };
 
diff --git a/packages/plugin-dts/src/utils.ts b/packages/plugin-dts/src/utils.ts
index 90168c4ff..320adef90 100644
--- a/packages/plugin-dts/src/utils.ts
+++ b/packages/plugin-dts/src/utils.ts
@@ -1,5 +1,7 @@
-import fs, { writeFileSync } from 'node:fs';
+import fs from 'node:fs';
 import path from 'node:path';
+import { logger } from '@rsbuild/core';
+import fg from 'fast-glob';
 import color from 'picocolors';
 import * as ts from 'typescript';
 
@@ -27,7 +29,7 @@ export function ensureTempDeclarationDir(cwd: string): string {
   fs.mkdirSync(dirPath, { recursive: true });
 
   const gitIgnorePath = path.join(cwd, `${TEMP_FOLDER}/.gitignore`);
-  writeFileSync(gitIgnorePath, '**/*\n');
+  fs.writeFileSync(gitIgnorePath, '**/*\n');
 
   return dirPath;
 }
@@ -43,3 +45,28 @@ export function getFileLoc(diagnostic: ts.Diagnostic): string {
 
   return '';
 }
+
+export function getTimeCost(start: number): string {
+  return `${Math.floor(Date.now() - start)}ms`;
+}
+
+export async function processDtsFiles(
+  bundle: boolean,
+  dir: string,
+  dtsExtension: string,
+): Promise<void> {
+  if (bundle) {
+    return;
+  }
+
+  const dtsFiles = await fg(`${dir}/**/*.d.ts`);
+
+  for (const file of dtsFiles) {
+    try {
+      const newFile = file.replace('.d.ts', dtsExtension);
+      fs.renameSync(file, newFile);
+    } catch (error) {
+      logger.error(`Error renaming DTS file ${file}: ${error}`);
+    }
+  }
+}
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index b4f9cbab7..7ab6872ab 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -100,6 +100,8 @@ importers:
 
   e2e/cases/dts/bundle: {}
 
+  e2e/cases/dts/bundle-false: {}
+
   e2e/scripts: {}
 
   examples/express-plugin:
@@ -177,6 +179,9 @@ importers:
 
   packages/plugin-dts:
     dependencies:
+      fast-glob:
+        specifier: ^3.3.2
+        version: 3.3.2
       picocolors:
         specifier: 1.0.1
         version: 1.0.1