diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9a3f2c9..731bac0 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 cos-php-sdk-v5 Upgrade Guide
 ====================
+2.6.5 to 2.6.6
+---------
+修复部分问题
+
 2.6.4 to 2.6.5
 ---------
 1. 文字水印支持scatype、spcent参数
diff --git a/src/Client.php b/src/Client.php
index d5651de..10a30a3 100644
--- a/src/Client.php
+++ b/src/Client.php
@@ -236,7 +236,7 @@
  * @see \Qcloud\Cos\Service::getService()
  */
 class Client extends GuzzleClient {
-    const VERSION = '2.6.5';
+    const VERSION = '2.6.6';
 
     public $httpClient;