diff --git a/openhands/resolver/send_pull_request.py b/openhands/resolver/send_pull_request.py
index a17bb846ee..e9513d256f 100644
--- a/openhands/resolver/send_pull_request.py
+++ b/openhands/resolver/send_pull_request.py
@@ -319,6 +319,12 @@ def send_pull_request(
         pr_body += f'\n\n{additional_message}'
     pr_body += '\n\nAutomatic fix generated by [OpenHands](https://github.com/All-Hands-AI/OpenHands/) 🙌'
 
+    # For cross repo pull request, we need to send head parameter like fork_owner:branch as per git documentation here : https://docs.github.com/en/rest/pulls/pulls?apiVersion=2022-11-28#create-a-pull-request
+    # head parameter usage : The name of the branch where your changes are implemented. For cross-repository pull requests in the same network, namespace head with a user like this: username:branch.
+    if fork_owner and platform == Platform.GITHUB:
+        head_branch = f'{fork_owner}:{branch_name}'
+    else:
+        head_branch = branch_name
     # If we are not sending a PR, we can finish early and return the
     # URL for the user to open a PR manually
     if pr_type == 'branch':
@@ -328,7 +334,7 @@ def send_pull_request(
         data = {
             'title': final_pr_title,
             ('body' if platform == Platform.GITHUB else 'description'): pr_body,
-            ('head' if platform == Platform.GITHUB else 'source_branch'): branch_name,
+            ('head' if platform == Platform.GITHUB else 'source_branch'): head_branch,
             ('base' if platform == Platform.GITHUB else 'target_branch'): base_branch,
             'draft': pr_type == 'draft',
         }
diff --git a/tests/unit/resolver/github/test_send_pull_request.py b/tests/unit/resolver/github/test_send_pull_request.py
index a57c14df4c..329002f44a 100644
--- a/tests/unit/resolver/github/test_send_pull_request.py
+++ b/tests/unit/resolver/github/test_send_pull_request.py
@@ -558,7 +558,7 @@ def test_send_pull_request_target_branch_with_fork(
     post_data = mock_post.call_args[1]['json']
     assert post_data['base'] == target_branch  # PR should target the specified branch
     assert (
-        post_data['head'] == 'openhands-fix-issue-42'
+        post_data['head'] == 'fork-owner:openhands-fix-issue-42'
     )  # Branch name should be standard
 
     # Check that push was to fork