diff --git a/app/models/banner.rb b/app/models/banner.rb
index 69d9733..186bca0 100644
--- a/app/models/banner.rb
+++ b/app/models/banner.rb
@@ -12,7 +12,7 @@ class Banner
   field :width, type: Integer
   field :base_image, type: Integer, default: 1
 
-  has_many :ad_images , dependent: :delete
+  has_many :ad_images , dependent: :destroy
 
   validates_uniqueness_of :title
   validates :title, :length => { :minimum => 2 }