diff --git a/app/models/registration.rb b/app/models/registration.rb
index 5d2555f2..8281c9cb 100644
--- a/app/models/registration.rb
+++ b/app/models/registration.rb
@@ -27,6 +27,7 @@ class Registration < ActiveRecord::Base
   validates :user_id, uniqueness: { scope: :conference_id, message: 'already Registered!' }
   validate :registration_limit_not_exceed, on: :create
   validate :registration_to_events_only_if_present
+  validate :before_end_of_registration_period, on: :create
 
   after_create :set_week, :subscribe_to_conference, :send_registration_mail
 
@@ -59,6 +60,12 @@ class Registration < ActiveRecord::Base
     end
   end
 
+  def before_end_of_registration_period
+    if conference && conference.registration_period && conference.registration_period.end_date && (Date.today > conference.registration_period.end_date)
+      errors.add(:created_at, "can't be after the registration period end date!")
+    end
+  end
+
   def subscribe_to_conference
     Subscription.create(conference_id: conference.id, user_id: user.id)
   end