diff --git a/lib/active_merchant/billing/gateways/moneris.rb b/lib/active_merchant/billing/gateways/moneris.rb
index 4e5487bf829..5484bb52c9e 100644
--- a/lib/active_merchant/billing/gateways/moneris.rb
+++ b/lib/active_merchant/billing/gateways/moneris.rb
@@ -14,7 +14,7 @@ class MonerisGateway < Gateway
       LIVE_URL = 'https://www3.moneris.com/gateway2/servlet/MpgRequest'
       
       self.supported_countries = ['CA']
-      self.supported_cardtypes = [:visa, :master, :american_express]
+      self.supported_cardtypes = [:visa, :master, :american_express, :diners_club, :discover]
       self.homepage_url = 'http://www.moneris.com/'
       self.display_name = 'Moneris'
   
diff --git a/test/unit/gateways/moneris_test.rb b/test/unit/gateways/moneris_test.rb
index e266b16999b..c59bd88f63d 100644
--- a/test/unit/gateways/moneris_test.rb
+++ b/test/unit/gateways/moneris_test.rb
@@ -101,7 +101,7 @@ def test_supported_countries
   end
   
   def test_supported_card_types
-    assert_equal [:visa, :master, :american_express], MonerisGateway.supported_cardtypes
+    assert_equal [:visa, :master, :american_express, :diners_club, :discover], MonerisGateway.supported_cardtypes
   end
 
   def test_should_raise_error_if_transaction_param_empty_on_credit_request