diff --git a/app/models/proposition.rb b/app/models/proposition.rb
index c3ab063..0fd16f2 100644
--- a/app/models/proposition.rb
+++ b/app/models/proposition.rb
@@ -1,6 +1,6 @@
 class Proposition < ActiveRecord::Base
   belongs_to :proposer, class_name: 'User'
-  belongs_to :proposable, polymorphic: true
+  belongs_to :proposable, polymorphic: true, dependent: :destroy
   enum status: [:undecided, :approved, :rejected, :backup]
   delegate :proposable_title, :proposable_type, :proposable_description, to: :proposable