diff --git a/gitlab/v4/objects/merge_requests.py b/gitlab/v4/objects/merge_requests.py
index dd118d0db..8bbd7870c 100644
--- a/gitlab/v4/objects/merge_requests.py
+++ b/gitlab/v4/objects/merge_requests.py
@@ -373,6 +373,7 @@ class ProjectMergeRequestManager(CRUDMixin, RESTManager):
             "remove_source_branch",
             "allow_maintainer_to_push",
             "squash",
+            "reviewer_ids",
         ),
     )
     _update_attrs = RequiredOptional(
@@ -388,6 +389,7 @@ class ProjectMergeRequestManager(CRUDMixin, RESTManager):
             "discussion_locked",
             "allow_maintainer_to_push",
             "squash",
+            "reviewer_ids",
         ),
     )
     _list_filters = (