diff --git a/common/data_source/gitlab_connector.py b/common/data_source/gitlab_connector.py
index 0d2c0dab77..dae24992b4 100644
--- a/common/data_source/gitlab_connector.py
+++ b/common/data_source/gitlab_connector.py
@@ -20,8 +20,11 @@ from common.data_source.interfaces import GenerateDocumentsOutput
 from common.data_source.interfaces import LoadConnector
 from common.data_source.interfaces import PollConnector
 from common.data_source.interfaces import SecondsSinceUnixEpoch
+from common.data_source.interfaces import SlimConnectorWithPermSync
 from common.data_source.models import BasicExpertInfo
 from common.data_source.models import Document
+from common.data_source.models import GenerateSlimDocumentOutput
+from common.data_source.models import SlimDocument
 from common.data_source.utils import get_file_ext
 
 T = TypeVar("T")
@@ -158,7 +161,7 @@ def _should_exclude(path: str) -> bool:
     return any(fnmatch.fnmatch(path, pattern) for pattern in exclude_patterns)
 
 
-class GitlabConnector(LoadConnector, PollConnector):
+class GitlabConnector(LoadConnector, PollConnector, SlimConnectorWithPermSync):
     def __init__(
         self,
         project_owner: str,
@@ -313,6 +316,67 @@ class GitlabConnector(LoadConnector, PollConnector):
         end_datetime = datetime.fromtimestamp(end, tz=timezone.utc)
         return self._fetch_from_gitlab(start_datetime, end_datetime)
 
+    def retrieve_all_slim_docs_perm_sync(self, callback: Any = None) -> GenerateSlimDocumentOutput:
+        if self.gitlab_client is None:
+            raise ConnectorMissingCredentialError("Gitlab")
+
+        project: Project = self.gitlab_client.projects.get(
+            f"{self.project_owner}/{self.project_name}"
+        )
+
+        slim_batch: list[SlimDocument] = []
+
+        def append_doc(doc_id: str):
+            slim_batch.append(SlimDocument(id=doc_id))
+            if len(slim_batch) >= self.batch_size:
+                batch = slim_batch[:]
+                slim_batch.clear()
+                return batch
+            return None
+
+        if self.include_code_files:
+            default_branch = project.default_branch
+            queue = deque([""])
+            while queue:
+                current_path = queue.popleft()
+                files = project.repository_tree(path=current_path, all=True)
+                for file in files:
+                    if _should_exclude(file["path"]):
+                        continue
+                    if file["type"] == "tree":
+                        queue.append(file["path"])
+                        continue
+                    if file["type"] != "blob":
+                        continue
+
+                    file_url = f"{self.gitlab_client.url}/{self.project_owner}/{self.project_name}/-/blob/{default_branch}/{file['path']}"
+                    batch = append_doc(file_url)
+                    if batch:
+                        yield batch
+
+        if self.include_mrs:
+            merge_requests = project.mergerequests.list(
+                state=self.state_filter,
+                iterator=True,
+            )
+            for mr in merge_requests:
+                batch = append_doc(mr.web_url)
+                if batch:
+                    yield batch
+
+        if self.include_issues:
+            issues = project.issues.list(
+                state=self.state_filter,
+                iterator=True,
+            )
+            for issue in issues:
+                batch = append_doc(issue.web_url)
+                if batch:
+                    yield batch
+
+        if slim_batch:
+            yield slim_batch
+
 
 if __name__ == "__main__":
     import os
@@ -337,4 +401,4 @@ if __name__ == "__main__":
     document_batches = connector.load_from_state()
     for f in document_batches:
         print("Batch:", f)
-    print("Finished loading from state.")
\ No newline at end of file
+    print("Finished loading from state.")
diff --git a/rag/svr/sync_data_source.py b/rag/svr/sync_data_source.py
index 6f160a3564..81ab42e7be 100644
--- a/rag/svr/sync_data_source.py
+++ b/rag/svr/sync_data_source.py
@@ -1305,6 +1305,7 @@ class Gitlab(SyncBase):
             }
         )
 
+        file_list = None
         if task["reindex"] == "1" or not task["poll_range_start"]:
             document_generator = self.connector.load_from_state()
             _begin_info = "totally"
@@ -1318,9 +1319,13 @@ class Gitlab(SyncBase):
                     poll_start.timestamp(),
                     datetime.now(timezone.utc).timestamp()
                 )
+                if self.conf.get("sync_deleted_files"):
+                    file_list = []
+                    for slim_batch in self.connector.retrieve_all_slim_docs_perm_sync():
+                        file_list.extend(slim_batch)
                 _begin_info = "from {}".format(poll_start)
         self.log_connection("Gitlab", f"({self.conf['project_name']})", task)
-        return document_generator
+        return document_generator, file_list
 
 
 class Bitbucket(SyncBase):
diff --git a/web/src/pages/user-setting/data-source/constant/index.tsx b/web/src/pages/user-setting/data-source/constant/index.tsx
index 5816193e54..78e0f59906 100644
--- a/web/src/pages/user-setting/data-source/constant/index.tsx
+++ b/web/src/pages/user-setting/data-source/constant/index.tsx
@@ -58,6 +58,9 @@ export const DataSourceFeatureVisibilityMap = {
   [DataSourceKey.GITHUB]: {
     syncDeletedFiles: true,
   },
+  [DataSourceKey.GITLAB]: {
+    syncDeletedFiles: true,
+  },
   [DataSourceKey.GOOGLE_DRIVE]: {
     syncDeletedFiles: true,
   },