diff --git a/app/models/namespace.rb b/app/models/namespace.rb
index f9b53b2b70a..bfa33dc86ac 100644
--- a/app/models/namespace.rb
+++ b/app/models/namespace.rb
@@ -250,7 +250,9 @@ class Namespace < ApplicationRecord
   end
 
   def root_ancestor
-    self_and_ancestors.reorder(nil).find_by(parent_id: nil)
+    strong_memoize(:root_ancestor) do
+      self_and_ancestors.reorder(nil).find_by(parent_id: nil)
+    end
   end
 
   def subgroup?