diff --git a/lib/rdoc/ruby_token.rb b/lib/rdoc/ruby_token.rb
index d64751bfbb..baab3fe836 100644
--- a/lib/rdoc/ruby_token.rb
+++ b/lib/rdoc/ruby_token.rb
@@ -322,6 +322,7 @@ def Token(token, value = nil)
     [:TklEND,       TkKW,  "END",      :EXPR_END],
     [:Tk__LINE__,   TkKW,  "__LINE__", :EXPR_END],
     [:Tk__FILE__,   TkKW,  "__FILE__", :EXPR_END],
+    [:Tk__ENCODING__,TkKW, "__ENCODING__", :EXPR_END],
 
     [:TkIDENTIFIER, TkId],
     [:TkFID,        TkId],
diff --git a/test/test_rdoc_ruby_lex.rb b/test/test_rdoc_ruby_lex.rb
index 3c47ff22de..544e0c7e7d 100644
--- a/test/test_rdoc_ruby_lex.rb
+++ b/test/test_rdoc_ruby_lex.rb
@@ -62,6 +62,17 @@ def test_class_tokenize___END__
     assert_equal expected, tokens
   end
 
+  def test_class_tokenize___ENCODING__
+    tokens = RDoc::RubyLex.tokenize '__ENCODING__', nil
+
+    expected = [
+      @TK::Tk__ENCODING__.new( 0, 1,  0, '__ENCODING__'),
+      @TK::TkNL          .new(12, 1, 12, "\n"),
+    ]
+
+    assert_equal expected, tokens
+  end
+
   def test_class_tokenize_character_literal
     tokens = RDoc::RubyLex.tokenize "?c", nil