diff --git a/actionpack/lib/action_dispatch/middleware/flash.rb b/actionpack/lib/action_dispatch/middleware/flash.rb
index 2ce7f841ce..87614af74f 100644
--- a/actionpack/lib/action_dispatch/middleware/flash.rb
+++ b/actionpack/lib/action_dispatch/middleware/flash.rb
@@ -272,7 +272,7 @@ module ActionDispatch
         env[KEY] = new_hash
       end
 
-      if session.key?('flash') && session['flash'].empty?
+      if session['flash'] && session['flash'].empty?
         session.delete('flash')
       end
     end