diff --git a/ChangeLog b/ChangeLog
index 1481bc064d..56a9bf1d88 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Thu Apr 14 19:02:41 2016  NARUSE, Yui  <naruse@ruby-lang.org>
+
+	* lib/irb/ext/save-history.rb: suppress warning: method redefined;
+	  discarding old save_history=.
+
 Thu Apr 14 14:58:14 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* ext/tk/tkutil/tkutil.c (tk_hash_kv): the third argument can be
diff --git a/lib/irb/ext/save-history.rb b/lib/irb/ext/save-history.rb
index 236f00fb93..d6e9be7415 100644
--- a/lib/irb/ext/save-history.rb
+++ b/lib/irb/ext/save-history.rb
@@ -27,6 +27,7 @@ module IRB
       IRB.conf[:SAVE_HISTORY]
     end
 
+    remove_method :save_history=
     # Sets <code>IRB.conf[:SAVE_HISTORY]</code> to the given +val+ and calls
     # #init_save_history with this context.
     #