diff --git a/application/api/controller/Cart.php b/application/api/controller/Cart.php
index 93991d9..a5c8277 100644
--- a/application/api/controller/Cart.php
+++ b/application/api/controller/Cart.php
@@ -56,7 +56,7 @@ class Cart extends Api
         $spec_sku  = new Litestoregoodsspec();
         $spec_info = $spec_sku->where('goods_spec_id', $sku_id)->find();
         if ($cart) {
-            if ( $number+ $cart['number'] > $spec_info['stock_num']) {
+            if ( $number > $spec_info['stock_num']) {
                 $this->error('库存不足');
             }
             $cart->setInc('number', $number);