diff --git a/data/class/helper/SC_Helper_Purchase.php b/data/class/helper/SC_Helper_Purchase.php
index 8f2d1be7c9..a14db3f51c 100644
--- a/data/class/helper/SC_Helper_Purchase.php
+++ b/data/class/helper/SC_Helper_Purchase.php
@@ -260,7 +260,8 @@ public static function getOrderTemp($uniqId)
     {
         $objQuery = SC_Query_Ex::getSingletonInstance();
 
-        return $objQuery->getRow('*', 'dtb_order_temp', 'order_temp_id = ?', [$uniqId]);
+        $result = $objQuery->getRow('*', 'dtb_order_temp', 'order_temp_id = ?', [$uniqId]);
+        return is_array($result) ? $result : []; // 必ず配列を返す
     }
 
     /**
diff --git a/tests/class/helper/SC_Helper_Purchase/SC_Helper_Purchase_getOrderTempTest.php b/tests/class/helper/SC_Helper_Purchase/SC_Helper_Purchase_getOrderTempTest.php
index ba100a8433..6b27c53afb 100644
--- a/tests/class/helper/SC_Helper_Purchase/SC_Helper_Purchase_getOrderTempTest.php
+++ b/tests/class/helper/SC_Helper_Purchase/SC_Helper_Purchase_getOrderTempTest.php
@@ -58,7 +58,7 @@ public function testGetOrderTemp存在しない受注IDを指定した場合結
     {
         $order_id = '9999';
 
-        $this->expected = null;
+        $this->expected = [];
         $this->actual = SC_Helper_Purchase::getOrderTemp($order_id);
 
         $this->verify();