diff --git a/app/services/staff_action_logger.rb b/app/services/staff_action_logger.rb
index 4793424b7bf..fdfc7f200b3 100644
--- a/app/services/staff_action_logger.rb
+++ b/app/services/staff_action_logger.rb
@@ -65,10 +65,12 @@ class StaffActionLogger
   def log_topic_deletion(deleted_topic, opts={})
     raise Discourse::InvalidParameters.new(:deleted_topic) unless deleted_topic && deleted_topic.is_a?(Topic)
 
+    user = delete_topic.user ? "#{deleted_topic.user.username} (#{deleted_topic.user.name})" : "(deleted user)"
+
     details = [
       "id: #{deleted_topic.id}",
       "created_at: #{deleted_topic.created_at}",
-      "user: #{deleted_topic.user.username} (#{deleted_topic.user.name})",
+      "user: #{user}",
       "title: #{deleted_topic.title}"
     ]