diff --git a/ChangeLog b/ChangeLog
index aa7578312c..e76ead4c1c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,7 +1,7 @@
 Mon May 23 15:52:07 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
 
 	* ext/bigdecimal/bigdecimal.c (isfinite): isfinite does not always
-	  exist.  fixed build error on Windows itroduced at r55123.
+	  exist.  fixed build error on Windows introduced at r55123.
 
 Mon May 23 13:19:41 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>