diff --git a/metagpt/roles/engineer.py b/metagpt/roles/engineer.py
index 6962b1bb5..5055037f5 100644
--- a/metagpt/roles/engineer.py
+++ b/metagpt/roles/engineer.py
@@ -270,11 +270,11 @@ class Engineer(Role):
         design_doc = None
         code_plan_and_change_doc = await self._get_any_code_plan_and_change() if await self._is_fixbug() else None
         for i in dependencies:
-            if str(i.parent) == TASK_FILE_REPO:
+            if str(i.parent.as_posix()) == TASK_FILE_REPO:
                 task_doc = await self.project_repo.docs.task.get(i.name)
-            elif str(i.parent) == SYSTEM_DESIGN_FILE_REPO:
+            elif str(i.parent.as_posix()) == SYSTEM_DESIGN_FILE_REPO:
                 design_doc = await self.project_repo.docs.system_design.get(i.name)
-            elif str(i.parent) == CODE_PLAN_AND_CHANGE_FILE_REPO:
+            elif str(i.parent.as_posix()) == CODE_PLAN_AND_CHANGE_FILE_REPO:
                 code_plan_and_change_doc = await self.project_repo.docs.code_plan_and_change.get(i.name)
         if not task_doc or not design_doc:
             logger.error(f'Detected source code "{filename}" from an unknown origin.')
diff --git a/metagpt/utils/dependency_file.py b/metagpt/utils/dependency_file.py
index 0a375051c..d34e7ae9a 100644
--- a/metagpt/utils/dependency_file.py
+++ b/metagpt/utils/dependency_file.py
@@ -91,7 +91,7 @@ class DependencyFile:
         try:
             key = Path(filename).relative_to(root).as_posix()
         except ValueError:
-            key = filename
+            key = Path(filename).as_posix()
         return set(self._dependencies.get(str(key), {}))
 
     def delete_file(self):