diff --git a/mrblib/rf/00filter/yaml.rb b/mrblib/rf/00filter/yaml.rb
index 4fecde5..b9e61d5 100644
--- a/mrblib/rf/00filter/yaml.rb
+++ b/mrblib/rf/00filter/yaml.rb
@@ -3,13 +3,17 @@ module Filter
     class Yaml < Base
       class << self
         def config
-          @config ||= Struct.new(:no_doc, :boolean_mode).new.tap do |config|
+          @config ||= Struct.new(:no_doc, :boolean_mode, :raw).new.tap do |config|
             config.no_doc = true
             config.boolean_mode = true
+            config.raw = false
           end
         end
 
         def configure(opt)
+          opt.on('-r', '--raw-string', 'output raw strings') do
+            config.raw = true
+          end
           opt.on('--disable-boolean-mode', 'consider true/false/null as yaml literal') do
             config.boolean_mode = false
           end
@@ -26,6 +30,10 @@ def boolean_mode?
           config.boolean_mode
         end
 
+        def raw?
+          config.raw
+        end
+
         def format(val, record)
           return unless yaml_obj = obj_to_yaml(val, record)
 
@@ -36,6 +44,12 @@ def format(val, record)
 
         def obj_to_yaml(val, record)
           case val
+          when String
+            if raw?
+              val
+            else
+              val.to_yaml(colorize:)
+            end
           when MatchData
             record.to_yaml(colorize:)
           when Regexp
diff --git a/spec/filter/yaml_spec.rb b/spec/filter/yaml_spec.rb
index 09479a4..5c006e4 100644
--- a/spec/filter/yaml_spec.rb
+++ b/spec/filter/yaml_spec.rb
@@ -14,12 +14,32 @@
   context 'with -r option' do
     describe 'Output string' do
       let(:input) { load_fixture('yaml/multibyte_string.yml') }
-      let(:output) { '🍣🍣🍣' }
+      let(:args) { '-t yaml -r _' }
+      let(:expect_output) { "🍣🍣🍣\n" }
 
-      before { run_rf('-t yaml -r _', input) }
+      it_behaves_like 'a successful exec'
+    end
 
-      it { expect(last_command_started).to be_successfully_executed }
-      it { expect(last_command_started).to have_output output_string_eq output }
+    describe 'Ouput yaml to JSON string' do
+      let(:input) { load_fixture('json/hash.json') }
+      let(:args) { '-t yaml -r "_.to_json(pretty_print: true)"' }
+      let(:expect_output) do
+        <<~OUTPUT
+          {
+            "foo": 1,
+            "bar": {
+              "baz": [
+                "a",
+                "b",
+                "c"
+              ]
+            },
+            "foo bar": "foo bar"
+          }
+        OUTPUT
+      end
+
+      it_behaves_like 'a successful exec'
     end
   end
 
diff --git a/spec/global_options/help_spec.rb b/spec/global_options/help_spec.rb
index d090fb1..2168cbd 100644
--- a/spec/global_options/help_spec.rb
+++ b/spec/global_options/help_spec.rb
@@ -31,6 +31,7 @@
         -m, --minify                     minify json output
 
       yaml options:
+        -r, --raw-string                 output raw strings
             --disable-boolean-mode       consider true/false/null as yaml literal
             --[no-]doc                   [no] output document sperator (refers to ---) (default:--no-doc)
     TEXT