diff --git a/lib/correios/cep/address.rb b/lib/correios/cep/address.rb
index dea08b9..e39055e 100644
--- a/lib/correios/cep/address.rb
+++ b/lib/correios/cep/address.rb
@@ -12,6 +12,8 @@ class Address
       element :complemento2, as: :complement2
 
       def ==(other)
+        return false unless other.is_a?(self.class)
+
         instance_variables.each do |attr|
           return false unless self.instance_variable_get(attr) == other.instance_variable_get(attr)
         end
diff --git a/spec/correios/cep/address_spec.rb b/spec/correios/cep/address_spec.rb
index ea2e33c..64a7a7b 100644
--- a/spec/correios/cep/address_spec.rb
+++ b/spec/correios/cep/address_spec.rb
@@ -43,6 +43,15 @@
 
       it { should be false }
     end
+
+    context 'when compares with other kind of object' do
+      subject do
+        address = described_class.new
+        address == :address
+      end
+
+      it { should be false }
+    end
   end
 
   describe '#has_content?' do