diff --git a/examples/test-test/utils/mjs.mjs b/examples/test-test/utils/mjs.mjs
new file mode 100644
index 000000000000..c874d5ad9aad
--- /dev/null
+++ b/examples/test-test/utils/mjs.mjs
@@ -0,0 +1,3 @@
+export default function mjs() {
+  return 'mjs'
+};
diff --git a/examples/test-test/utils/mjs.test.ts b/examples/test-test/utils/mjs.test.ts
new file mode 100644
index 000000000000..2fd212b31203
--- /dev/null
+++ b/examples/test-test/utils/mjs.test.ts
@@ -0,0 +1,5 @@
+import mjs from './mjs.mjs';
+
+it('imports from mjs', () => {
+  expect(mjs()).toBe('mjs');
+});
diff --git a/packages/testing/src/index.ts b/packages/testing/src/index.ts
index 3d2e1fd7a1fa..aab459daa631 100644
--- a/packages/testing/src/index.ts
+++ b/packages/testing/src/index.ts
@@ -73,6 +73,10 @@ export function createConfig(opts?: {
         opts?.jsTransformer || 'esbuild',
         opts?.jsTransformerOpts,
       ),
+      '^.+\\.mjs$': getJSTransformer(
+        opts?.jsTransformer || 'esbuild',
+        opts?.jsTransformerOpts,
+      ),
     },
     moduleNameMapper: {
       '^.+\\.(css|less|sass|scss|stylus)$':
diff --git a/packages/testing/src/transformers/esbuild/index.ts b/packages/testing/src/transformers/esbuild/index.ts
index dfd22f7743e6..daed4d76694a 100644
--- a/packages/testing/src/transformers/esbuild/index.ts
+++ b/packages/testing/src/transformers/esbuild/index.ts
@@ -11,7 +11,9 @@ const TS_TSX_REGEX = /\.tsx?$/;
 const JS_JSX_REGEX = /\.jsx?$/;
 
 function isTarget(path: string) {
-  return JS_JSX_REGEX.test(path) || TS_TSX_REGEX.test(path);
+  return (
+    JS_JSX_REGEX.test(path) || TS_TSX_REGEX.test(path) || path.endsWith('.mjs')
+  );
 }
 
 const createTransformer = (
@@ -70,7 +72,7 @@ const createTransformer = (
       const result = transformSync(rawCode, {
         ...options,
         ...(config.globals['jest-esbuild'] as UserOptions),
-        loader: userOptions.loader || (extname(path).slice(1) as Loader),
+        loader: userOptions.loader || ext2Loader(extname(path)),
         sourcefile: path,
         sourcesContent: false,
       });
@@ -100,6 +102,18 @@ const createTransformer = (
   };
 };
 
+const EXT_MAP: Record<string, Loader> = {
+  '.js': 'js',
+  '.jsx': 'jsx',
+  '.ts': 'ts',
+  '.tsx': 'tsx',
+  '.mjs': 'js',
+};
+
+function ext2Loader(ext: string): Loader {
+  return EXT_MAP[ext] || 'js';
+}
+
 export default {
   createTransformer,
 };