diff --git a/lib/active_model/serializer/associations.rb b/lib/active_model/serializer/associations.rb
index 13678ade..e05f2a33 100644
--- a/lib/active_model/serializer/associations.rb
+++ b/lib/active_model/serializer/associations.rb
@@ -39,7 +39,8 @@ module ActiveModel
         end
 
         def target_serializer
-          option(:serializer)
+          serializer = option(:serializer)
+          serializer.is_a?(String) ? serializer.constantize : serializer
         end
 
         def source_serializer
diff --git a/test/association_test.rb b/test/association_test.rb
index 349a374c..b56b124c 100644
--- a/test/association_test.rb
+++ b/test/association_test.rb
@@ -392,4 +392,26 @@ class AssociationTest < ActiveModel::TestCase
       }, json)
     end
   end
+
+  class StringSerializerOption < AssociationTest
+    class StringSerializer < ActiveModel::Serializer
+      attributes :id, :body
+    end
+
+    def test_specifying_serializer_class_as_string
+      @post_serializer_class.class_eval do
+        has_many :comments, :embed => :objects
+      end
+
+      include_bare! :comments, :serializer => "AssociationTest::StringSerializerOption::StringSerializer"
+
+      assert_equal({
+        :comments => [
+          { :id => 1, :body => "ZOMG A COMMENT" }
+        ]
+      }, @hash)
+
+      assert_equal({}, @root_hash)
+    end
+  end
 end