diff --git a/django/contrib/comments/admin.py b/django/contrib/comments/admin.py
index 3b1fb14bcc..c2f8e564f4 100644
--- a/django/contrib/comments/admin.py
+++ b/django/contrib/comments/admin.py
@@ -20,6 +20,7 @@ class CommentsAdmin(admin.ModelAdmin):
     list_filter = ('submit_date', 'site', 'is_public', 'is_removed')
     date_hierarchy = 'submit_date'
     ordering = ('-submit_date',)
+    raw_id_fields = ('user',)
     search_fields = ('comment', 'user__username', 'user_name', 'user_email', 'user_url', 'ip_address')
 
 # Only register the default admin if the model is the built-in comment model