diff --git a/ChangeLog b/ChangeLog
index d364242095..6637f0c01c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Thu Oct 10 21:36:16 2013  Masaki Matsushita  <glass.saga@gmail.com>
+
+	* array.c (rb_ary_compact_bang): use ary_resize_smaller().
+
 Thu Oct 10 21:00:38 2013  Masaki Matsushita  <glass.saga@gmail.com>
 
 	* st.c (st_keys): define st_keys() for performance improvement of
diff --git a/array.c b/array.c
index 7e8617b771..c45c992840 100644
--- a/array.c
+++ b/array.c
@@ -4166,10 +4166,7 @@ rb_ary_compact_bang(VALUE ary)
     if (RARRAY_LEN(ary) == n) {
 	return Qnil;
     }
-    ARY_SET_LEN(ary, n);
-    if (n * 2 < ARY_CAPA(ary) && ARY_DEFAULT_SIZE * 2 < ARY_CAPA(ary)) {
-	ary_resize_capa(ary, n * 2);
-    }
+    ary_resize_smaller(ary, n);
 
     return ary;
 }