diff --git a/git/objects/submodule/base.py b/git/objects/submodule/base.py
index 7e8dd053e..f9b0b6ad6 100644
--- a/git/objects/submodule/base.py
+++ b/git/objects/submodule/base.py
@@ -293,7 +293,8 @@ def _write_git_file_and_module_config(cls, working_tree_dir, module_abspath):
         fp.close()
 
         writer = GitConfigParser(os.path.join(module_abspath, 'config'), read_only=False, merge_includes=False)
-        writer.set_value('core', 'worktree', os.path.relpath(working_tree_dir, start=module_abspath))
+        writer.set_value('core', 'worktree',
+                         to_native_path_linux(os.path.relpath(working_tree_dir, start=module_abspath)))
         writer.release()
 
     #{ Edit Interface