diff --git a/lib/irb/color.rb b/lib/irb/color.rb
index 02f1e29ea..3e9b59532 100644
--- a/lib/irb/color.rb
+++ b/lib/irb/color.rb
@@ -69,6 +69,7 @@ module Color
       KEYWORD_IN:         [GREEN],
       KEYWORD_DEF:        [GREEN],
       KEYWORD_DO:         [GREEN],
+      KEYWORD_DO_BLOCK:   [GREEN],
       KEYWORD_DO_LOOP:    [GREEN],
       KEYWORD_FOR:        [GREEN],
       KEYWORD_BEGIN:      [GREEN],
diff --git a/test/irb/test_color.rb b/test/irb/test_color.rb
index 407f02d8d..5cb036549 100644
--- a/test/irb/test_color.rb
+++ b/test/irb/test_color.rb
@@ -135,6 +135,8 @@ def test_colorize_code
         'Foo.Bar(1)' => "#{BLUE}#{BOLD}#{UNDERLINE}Foo#{CLEAR}.#{CYAN}Bar#{CLEAR}(#{BLUE}#{BOLD}1#{CLEAR})",
         'Foo&.Bar(1)' => "#{BLUE}#{BOLD}#{UNDERLINE}Foo#{CLEAR}&.#{CYAN}Bar#{CLEAR}(#{BLUE}#{BOLD}1#{CLEAR})",
         'ENV' => "#{BLUE}#{BOLD}#{UNDERLINE}ENV#{CLEAR}",
+        'f do end' => "#{CYAN}f#{CLEAR} #{GREEN}do#{CLEAR} #{GREEN}end#{CLEAR}",
+        'f true do end' => "#{CYAN}f#{CLEAR} #{CYAN}#{BOLD}true#{CLEAR} #{GREEN}do#{CLEAR} #{GREEN}end#{CLEAR}",
       }
 
       tests.each do |code, result|