diff --git a/packages/playwright-core/src/client/browserType.ts b/packages/playwright-core/src/client/browserType.ts
index 1a37ee6724..59ce8c56d7 100644
--- a/packages/playwright-core/src/client/browserType.ts
+++ b/packages/playwright-core/src/client/browserType.ts
@@ -14,6 +14,8 @@
  * limitations under the License.
  */
 
+import path from 'path';
+
 import { Browser } from './browser';
 import { BrowserContext, prepareBrowserContextParams } from './browserContext';
 import { ChannelOwner } from './channelOwner';
@@ -98,7 +100,7 @@ export class BrowserType extends ChannelOwner<channels.BrowserTypeChannel> imple
       ignoreAllDefaultArgs: !!options.ignoreDefaultArgs && !Array.isArray(options.ignoreDefaultArgs),
       env: options.env ? envObjectToArray(options.env) : undefined,
       channel: options.channel,
-      userDataDir,
+      userDataDir: path.isAbsolute(userDataDir) ? userDataDir : path.resolve(userDataDir),
     };
     return await this._wrapApiCall(async () => {
       const result = await this._channel.launchPersistentContext(persistentParams);
diff --git a/packages/playwright-core/src/server/browserType.ts b/packages/playwright-core/src/server/browserType.ts
index 509fb4cc4f..19c40e7813 100644
--- a/packages/playwright-core/src/server/browserType.ts
+++ b/packages/playwright-core/src/server/browserType.ts
@@ -20,7 +20,7 @@ import * as path from 'path';
 
 import { normalizeProxySettings, validateBrowserContextOptions } from './browserContext';
 import { DEFAULT_TIMEOUT, TimeoutSettings } from '../common/timeoutSettings';
-import { ManualPromise, debugMode } from '../utils';
+import { ManualPromise, assert, debugMode } from '../utils';
 import { existsAsync } from './fileUtils';
 import { helper } from './helper';
 import { SdkObject } from './instrumentation';
@@ -188,6 +188,7 @@ export abstract class BrowserType extends SdkObject {
     tempDirectories.push(artifactsDir);
 
     if (userDataDir) {
+      assert(path.isAbsolute(userDataDir), 'userDataDir must be an absolute path');
       // Firefox bails if the profile directory does not exist, Chrome creates it. We ensure consistent behavior here.
       if (!await existsAsync(userDataDir))
         await fs.promises.mkdir(userDataDir, { recursive: true, mode: 0o700 });
diff --git a/tests/library/defaultbrowsercontext-2.spec.ts b/tests/library/defaultbrowsercontext-2.spec.ts
index e16dc6b0ba..f3f273724a 100644
--- a/tests/library/defaultbrowsercontext-2.spec.ts
+++ b/tests/library/defaultbrowsercontext-2.spec.ts
@@ -101,6 +101,13 @@ it('should accept userDataDir', async ({ createUserDataDir, browserType }) => {
   expect(fs.readdirSync(userDataDir).length).toBeGreaterThan(0);
 });
 
+it('should accept relative userDataDir', async ({ createUserDataDir, browserType }) => {
+  const userDataDir = await createUserDataDir();
+  const context = await browserType.launchPersistentContext(path.relative(process.cwd(), path.join(userDataDir, 'foobar')));
+  expect(fs.readdirSync(path.join(userDataDir, 'foobar')).length).toBeGreaterThan(0);
+  await context.close();
+});
+
 it('should restore state from userDataDir', async ({ browserType, server, createUserDataDir, isMac, browserName }) => {
   it.slow();