1 files changed, 9 insertions, 1 deletions
diff --git a/lib/gitlab/bitbucket_server_import/importers/pull_request_importer.rb b/lib/gitlab/bitbucket_server_import/importers/pull_request_importer.rb
index 34963452192..0d4de385f5e 100644
--- a/lib/gitlab/bitbucket_server_import/importers/pull_request_importer.rb
+++ b/lib/gitlab/bitbucket_server_import/importers/pull_request_importer.rb
@@ -30,7 +30,7 @@ module Gitlab
             reviewer_ids: reviewers,
             source_project_id: project.id,
             source_branch: Gitlab::Git.ref_name(object[:source_branch_name]),
-            source_branch_sha: object[:source_branch_sha],
+            source_branch_sha: source_branch_sha,
             target_project_id: project.id,
             target_branch: Gitlab::Git.ref_name(object[:target_branch_name]),
             target_branch_sha: object[:target_branch_sha],
@@ -68,6 +68,14 @@ module Gitlab
             end
           end
         end
+
+        def source_branch_sha
+          source_branch_sha = project.repository.commit(object[:source_branch_sha])&.sha
+
+          return source_branch_sha if source_branch_sha
+
+          project.repository.find_commits_by_message(object[:source_branch_sha])&.first&.sha
+        end
       end
     end
   end