diff --git a/reference/pdo/pdo.xml b/reference/pdo/pdo.xml
index a07cc21fcb..3645db3769 100644
--- a/reference/pdo/pdo.xml
+++ b/reference/pdo/pdo.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- $Revision$ -->
-<!-- EN-Revision: 14767af0f05dffa6fdb9b49e1a1f4e9ca7022a60 Maintainer: shimooka Status: ready -->
+<!-- EN-Revision: a78c7290730ac918c4eb6b199004d24051d1e93f Maintainer: shimooka Status: ready -->
 <!-- CREDITS: hirokawa,takagi -->
 <reference xml:id="class.pdo" role="class" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xi="http://www.w3.org/2001/XInclude">
  <title>PDO クラス</title>
@@ -487,6 +487,28 @@
    </classsynopsis>
   </section>
 
+  <section role="changelog" xml:id="pdo.changelog">
+   &reftitle.changelog;
+   <informaltable>
+    <tgroup cols="2">
+     <thead>
+      <row>
+       <entry>&Version;</entry>
+       <entry>&Description;</entry>
+      </row>
+     </thead>
+     <tbody>
+      <row>
+       <entry>8.4.0</entry>
+       <entry>
+        クラス定数が型付けされました。
+       </entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </informaltable>
+  </section>
+
  </partintro>
  
  &reference.pdo.entities.pdo;