diff --git a/test/test_bson.rb b/test/test_bson.rb
index 964a102..ff57216 100644
--- a/test/test_bson.rb
+++ b/test/test_bson.rb
@@ -1,4 +1,4 @@
-# coding:utf-8
+# encoding:utf-8
 require 'test/test_helper'
 
 class BSONTest < Test::Unit::TestCase