diff --git a/ChangeLog b/ChangeLog
index 14728051ff..1b83be546a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Sat Nov 14 17:00:13 2015  Tanaka Akira  <akr@fsij.org>
+
+	* lib/time.rb: Specify frozen_string_literal: true.
+
 Sat Nov 14 16:43:02 2015  Tanaka Akira  <akr@fsij.org>
 
 	* lib/open3.rb: Specify frozen_string_literal: true.
diff --git a/lib/time.rb b/lib/time.rb
index 07196a3c23..2ab069509c 100644
--- a/lib/time.rb
+++ b/lib/time.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'date'
 
 # = time.rb
diff --git a/test/test_time.rb b/test/test_time.rb
index 5f7ff1ad72..0a6659f152 100644
--- a/test/test_time.rb
+++ b/test/test_time.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'time'
 require 'test/unit'