diff --git a/mobile/plugins/payment/wxpay.php b/mobile/plugins/payment/wxpay.php
index fcd96e1..7c143a8 100755
--- a/mobile/plugins/payment/wxpay.php
+++ b/mobile/plugins/payment/wxpay.php
@@ -138,7 +138,7 @@ class wxpay
         $appId = $payinfo['appId'];
         $timeStamp = $payinfo['timeStamp'];
         $nonceStr = $payinfo['nonceStr'];
-        $signType = $payinfo['SignType'];
+        $signType = $payinfo['signType'];
         $paySign = $payinfo['paySign'];
         // ....实现自己的$this->getPrepayId()