diff --git a/src/Gateway.php b/src/Gateway.php
index 83dcc64..183fa64 100644
--- a/src/Gateway.php
+++ b/src/Gateway.php
@@ -8,6 +8,7 @@
 use Omnipay\Gomypay\Message\FetchTransactionRequest;
 use Omnipay\Gomypay\Message\GetPaymentInfoRequest;
 use Omnipay\Gomypay\Message\PurchaseRequest;
+use Omnipay\Gomypay\Message\VoidRequest;
 use Omnipay\Gomypay\Traits\HasGomypay;
 
 /**
@@ -51,6 +52,11 @@ public function fetchTransaction(array $options = [])
         return $this->createRequest(FetchTransactionRequest::class, $options);
     }
 
+    public function void(array $options = [])
+    {
+        return $this->createRequest(VoidRequest::class, $options);
+    }
+
     public function getPaymentInfo(array $options = [])
     {
         return $this->createRequest(GetPaymentInfoRequest::class, $options);
diff --git a/src/Message/FetchTransactionRequest.php b/src/Message/FetchTransactionRequest.php
index 801a933..2c0ffa5 100644
--- a/src/Message/FetchTransactionRequest.php
+++ b/src/Message/FetchTransactionRequest.php
@@ -24,7 +24,7 @@ public function sendData($data)
         $response = $this->httpClient->request(
             'POST',
             $this->getUrl('CallOrder.aspx'),
-            ['content-type' => 'application/json'],
+            ['content-type' => 'application/x-www-form-urlencoded'],
             http_build_query($data)
         );
         $data = json_decode((string) $response->getBody(), true);
diff --git a/src/Message/VoidRequest.php b/src/Message/VoidRequest.php
new file mode 100644
index 0000000..b7ddaf8
--- /dev/null
+++ b/src/Message/VoidRequest.php
@@ -0,0 +1,62 @@
+<?php
+
+namespace Omnipay\Gomypay\Message;
+
+use Omnipay\Gomypay\Traits\HasGomypay;
+use Omnipay\Gomypay\Traits\HasOrderNo;
+
+class VoidRequest extends AbstractRequest
+{
+    use HasGomypay;
+    use HasOrderNo;
+
+    public function getGoodsReturn()
+    {
+        return $this->getParameter('Goods_Return');
+    }
+
+    /**
+     * 退貨註記請填 1(申請退貨)
+     */
+    public function setGoodsRetrun($value)
+    {
+        return $this->setParameter('Goods_Return', $value);
+    }
+
+    public function getGoodsReturnReason()
+    {
+        return $this->getParameter('Goods_Return_Reason');
+    }
+
+    /**
+     * 退貨原因
+     */
+    public function setGoodsReturnReason($value)
+    {
+        return $this->setParameter('Goods_Return_Reason', $value);
+    }
+
+    public function getData()
+    {
+        return [
+            'Order_No' => $this->getTransactionId(),
+            'CustomerId' => $this->getCustomerId(),
+            'Str_Check' => $this->getStrCheck(),
+            'Goods_Return' => $this->getGoodsReturn() ?: 1,
+            'Goods_Return_Reason' => $this->getGoodsReturnReason() ?: '退貨',
+        ];
+    }
+
+    public function sendData($data)
+    {
+        $response = $this->httpClient->request(
+            'POST',
+            $this->getUrl('GoodReturn.aspx'),
+            ['content-type' => 'application/x-www-form-urlencoded'],
+            http_build_query($data)
+        );
+        $data = json_decode((string) $response->getBody(), true);
+
+        return $this->response = new VoidResponse($this, $data);
+    }
+}
diff --git a/src/Message/VoidResponse.php b/src/Message/VoidResponse.php
new file mode 100644
index 0000000..e71346a
--- /dev/null
+++ b/src/Message/VoidResponse.php
@@ -0,0 +1,21 @@
+<?php
+
+namespace Omnipay\Gomypay\Message;
+
+class VoidResponse extends AbstractResponse
+{
+    public function isSuccessful()
+    {
+        return false;
+    }
+
+    public function getCode()
+    {
+        return $this->data['result'];
+    }
+
+    public function getMessage()
+    {
+        return $this->data['ret_msg'];
+    }
+}
diff --git a/tests/Message/VoidRequestTest.php b/tests/Message/VoidRequestTest.php
new file mode 100644
index 0000000..7ada723
--- /dev/null
+++ b/tests/Message/VoidRequestTest.php
@@ -0,0 +1,38 @@
+<?php
+
+namespace Omnipay\Gomypay\Tests\Message;
+
+use Omnipay\Gomypay\Message\VoidRequest;
+use Omnipay\Tests\TestCase;
+
+class VoidRequestTest extends TestCase
+{
+    /**
+     * @var VoidRequest
+     */
+    private $request;
+
+    public function setUp(): void
+    {
+        parent::setUp();
+
+        $this->request = new VoidRequest($this->getHttpClient(), $this->getHttpRequest());
+        $this->request->initialize([
+            'CustomerId' => '42816104A05',
+            'Str_Check' => '2b1bef9d8ab6a81e9a2739c6ecc64ef8',
+            'test_mode' => true,
+
+            'transaction_id' => 'AH15482399052114',
+        ]);
+    }
+
+    public function testGetData()
+    {
+        $this->setMockHttpResponse('VoidSuccess.txt');
+        $response = $this->request->send();
+
+        $this->assertFalse($response->isSuccessful());
+        $this->assertEquals('申請退貨完成', $response->getMessage());
+        $this->assertEquals('1', $response->getCode());
+    }
+}
diff --git a/tests/Mock/VoidSuccess.txt b/tests/Mock/VoidSuccess.txt
new file mode 100644
index 0000000..5595917
--- /dev/null
+++ b/tests/Mock/VoidSuccess.txt
@@ -0,0 +1,7 @@
+HTTP/1.1 200 OK
+Server: Apache
+Date: Sun, 11 May 2014 21:17:31 GMT
+Content-Type: application/json; charset=utf-8
+Status: 200 OK
+
+{"result":"1","ret_msg":"申請退貨完成"}