diff --git a/aliyun/rds/connection.py b/aliyun/rds/connection.py
index 15307d6..22ec405 100644
--- a/aliyun/rds/connection.py
+++ b/aliyun/rds/connection.py
@@ -104,12 +104,12 @@ def get_dbinstance(self, instance_id):
             resp['DBInstanceId'],
             resp['RegionId'],
             resp['DBInstanceClass'],
-            resp['DBInstanceDescription'],
+            resp['DBInstanceDescription'] if resp.has_key("DBInstanceDescription") else 'None',
             resp['DBInstanceStatus'],
             resp['SecurityIPList'],
             resp['CreationTime'],
             resp['ExpireTime'],
-            resp['PayType'],
+            resp['PayType'] if resp.has_key("PayType") else 'None',
             resp['ConnectionString'],
             resp['DBInstanceNetType'],
             resp['MaxConnections'],