diff --git a/packages/core/src/config.ts b/packages/core/src/config.ts
index d26fcf0df..ddf50e716 100644
--- a/packages/core/src/config.ts
+++ b/packages/core/src/config.ts
@@ -5,7 +5,7 @@ import {
   mergeRsbuildConfig,
 } from '@rsbuild/core';
 import { dirname, isAbsolute, join, resolve } from 'pathe';
-import type { NormalizedConfig, RstestConfig } from './types';
+import type { NormalizedConfig, ProjectConfig, RstestConfig } from './types';
 import {
   castArray,
   color,
@@ -76,6 +76,12 @@ export async function loadConfig({
   return { content: content as RstestConfig, filePath: configFilePath };
 }
 
+export const mergeProjectConfig = (
+  ...configs: ProjectConfig[]
+): ProjectConfig => {
+  return mergeRstestConfig(...configs) as ProjectConfig;
+};
+
 export const mergeRstestConfig = (...configs: RstestConfig[]): RstestConfig => {
   return configs.reduce<RstestConfig>((result, config) => {
     const merged = mergeRsbuildConfig(result, {
diff --git a/packages/core/src/index.ts b/packages/core/src/index.ts
index 40f2bbf47..a93781d20 100644
--- a/packages/core/src/index.ts
+++ b/packages/core/src/index.ts
@@ -8,7 +8,7 @@ import type {
 } from './types';
 
 export { initCli, runCLI } from './cli';
-export { loadConfig, mergeRstestConfig } from './config';
+export { loadConfig, mergeProjectConfig, mergeRstestConfig } from './config';
 export { createRstest } from './core';
 
 export * from './runtime/api/public';