diff --git a/changelog.d/6235.bugfix b/changelog.d/6235.bugfix
new file mode 100644
index 000000000..12718ba93
--- /dev/null
+++ b/changelog.d/6235.bugfix
@@ -0,0 +1 @@
+Remove a room from a server's public rooms list on room upgrade.
\ No newline at end of file
diff --git a/synapse/handlers/room_member.py b/synapse/handlers/room_member.py
index 06d09c294..01c65ee22 100644
--- a/synapse/handlers/room_member.py
+++ b/synapse/handlers/room_member.py
@@ -514,6 +514,15 @@ class RoomMemberHandler(object):
         if old_room and old_room["is_public"]:
             yield self.store.set_room_is_public(old_room_id, False)
             yield self.store.set_room_is_public(room_id, True)
+            
+        # Check if any groups we own contain the predecessor room
+        local_group_ids = yield self.store.get_local_groups_for_room(old_room_id)
+        for group_id in local_group_ids:
+            # Add new the new room to those groups
+            yield self.store.add_room_to_group(group_id, room_id, old_room["is_public"])
+
+            # Remove the old room from those groups
+            yield self.store.remove_room_from_group(group_id, old_room_id)
 
     @defer.inlineCallbacks
     def copy_user_state_on_room_upgrade(self, old_room_id, new_room_id, user_ids):
diff --git a/synapse/storage/data_stores/main/group_server.py b/synapse/storage/data_stores/main/group_server.py
index b3a2771f1..13ad71a49 100644
--- a/synapse/storage/data_stores/main/group_server.py
+++ b/synapse/storage/data_stores/main/group_server.py
@@ -552,6 +552,21 @@ class GroupServerStore(SQLBaseStore):
             keyvalues={"group_id": group_id, "role_id": role_id, "user_id": user_id},
             desc="remove_user_from_summary",
         )
+    
+    def get_local_groups_for_room(self, room_id):
+        """Get all of the local group that contain a given room
+        Args:
+            room_id (str): The ID of a room
+        Returns:
+            Deferred[list[str]]: A twisted.Deferred containing a list of group ids
+                containing this room
+        """
+        return self._simple_select_onecol(
+            table="group_rooms",
+            keyvalues={"room_id": room_id},
+            retcol="group_id",
+            desc="get_local_groups_for_room",
+        )
 
     def get_users_for_summary_by_role(self, group_id, include_private=False):
         """Get the users and roles that should be included in a summary request