diff --git a/weixin-java-pay/src/main/java/com/github/binarywang/wxpay/config/WxPayConfig.java b/weixin-java-pay/src/main/java/com/github/binarywang/wxpay/config/WxPayConfig.java
index 2cfec2bc1..75db10a07 100644
--- a/weixin-java-pay/src/main/java/com/github/binarywang/wxpay/config/WxPayConfig.java
+++ b/weixin-java-pay/src/main/java/com/github/binarywang/wxpay/config/WxPayConfig.java
@@ -300,13 +300,13 @@ public class WxPayConfig {
       this.certSerialNo = certificate.getSerialNumber().toString(16).toUpperCase();
     }
     try {
-      if (merchantPrivateKey == null) {
+      if (merchantPrivateKey == null && StringUtils.isNotBlank(this.getPrivateKeyPath())) {
         try (InputStream keyInputStream = this.loadConfigInputStream(this.getPrivateKeyString(), this.getPrivateKeyPath(),
           this.privateKeyContent, "privateKeyPath")) {
           merchantPrivateKey = PemUtils.loadPrivateKey(keyInputStream);
         }
       }
-      if (certificate == null && StringUtils.isBlank(this.getCertSerialNo())) {
+      if (certificate == null && StringUtils.isBlank(this.getCertSerialNo()) && StringUtils.isNotBlank(this.getPrivateCertPath())) {
         try (InputStream certInputStream = this.loadConfigInputStream(this.getPrivateCertString(), this.getPrivateCertPath(),
           this.privateCertContent, "privateCertPath")) {
           certificate = PemUtils.loadCertificate(certInputStream);
diff --git a/weixin-java-pay/src/main/java/com/github/binarywang/wxpay/service/impl/WxPayServiceApacheHttpImpl.java b/weixin-java-pay/src/main/java/com/github/binarywang/wxpay/service/impl/WxPayServiceApacheHttpImpl.java
index f57ff13d4..f273fe1f9 100644
--- a/weixin-java-pay/src/main/java/com/github/binarywang/wxpay/service/impl/WxPayServiceApacheHttpImpl.java
+++ b/weixin-java-pay/src/main/java/com/github/binarywang/wxpay/service/impl/WxPayServiceApacheHttpImpl.java
@@ -44,6 +44,7 @@ public class WxPayServiceApacheHttpImpl extends BaseWxPayServiceImpl {
   private static final String ACCEPT = "Accept";
   private static final String CONTENT_TYPE = "Content-Type";
   private static final String APPLICATION_JSON = "application/json";
+  private static final String WECHATPAY_SERIAL = "Wechatpay-Serial";
 
   @Override
   public byte[] postForBytes(String url, String requestStr, boolean useKey) throws WxPayException {
@@ -101,7 +102,7 @@ public class WxPayServiceApacheHttpImpl extends BaseWxPayServiceImpl {
     httpPost.addHeader(ACCEPT, APPLICATION_JSON);
     httpPost.addHeader(CONTENT_TYPE, APPLICATION_JSON);
     String serialNumber = getWechatpaySerial(getConfig());
-    httpPost.addHeader("Wechatpay-Serial", serialNumber);
+    httpPost.addHeader(WECHATPAY_SERIAL, serialNumber);
     try (CloseableHttpResponse response = httpClient.execute(httpPost)) {
       //v3已经改为通过状态码判断200 204 成功
       int statusCode = response.getStatusLine().getStatusCode();
@@ -133,6 +134,8 @@ public class WxPayServiceApacheHttpImpl extends BaseWxPayServiceImpl {
   public String patchV3(String url, String requestStr) throws WxPayException {
     CloseableHttpClient httpClient = this.createApiV3HttpClient();
     HttpPatch httpPatch = new HttpPatch(url);
+    String serialNumber = getWechatpaySerial(getConfig());
+    httpPatch.addHeader(WECHATPAY_SERIAL, serialNumber);
     httpPatch.setEntity(this.createEntry(requestStr));
 
     httpPatch.setConfig(RequestConfig.custom()
@@ -204,6 +207,8 @@ public class WxPayServiceApacheHttpImpl extends BaseWxPayServiceImpl {
 
   @Override
   public String postV3(String url, HttpPost httpPost) throws WxPayException {
+    String serialNumber = getWechatpaySerial(getConfig());
+    httpPost.addHeader(WECHATPAY_SERIAL, serialNumber);
     return this.requestV3(url, httpPost);
   }
 
@@ -249,6 +254,8 @@ public class WxPayServiceApacheHttpImpl extends BaseWxPayServiceImpl {
     HttpGet httpGet = new HttpGet(url);
     httpGet.addHeader(ACCEPT, APPLICATION_JSON);
     httpGet.addHeader(CONTENT_TYPE, APPLICATION_JSON);
+    String serialNumber = getWechatpaySerial(getConfig());
+    httpGet.addHeader(WECHATPAY_SERIAL, serialNumber);
     return this.requestV3(url, httpGet);
   }
 
@@ -258,7 +265,7 @@ public class WxPayServiceApacheHttpImpl extends BaseWxPayServiceImpl {
     httpGet.addHeader(ACCEPT, APPLICATION_JSON);
     httpGet.addHeader(CONTENT_TYPE, APPLICATION_JSON);
     String serialNumber = getWechatpaySerial(getConfig());
-    httpGet.addHeader("Wechatpay-Serial", serialNumber);
+    httpGet.addHeader(WECHATPAY_SERIAL, serialNumber);
     return this.requestV3(url, httpGet);
   }
 
@@ -267,6 +274,8 @@ public class WxPayServiceApacheHttpImpl extends BaseWxPayServiceImpl {
     CloseableHttpClient httpClient = this.createApiV3HttpClient();
     HttpGet httpGet = new WxPayV3DownloadHttpGet(url);
     httpGet.addHeader(ACCEPT, ContentType.WILDCARD.getMimeType());
+    String serialNumber = getWechatpaySerial(getConfig());
+    httpGet.addHeader(WECHATPAY_SERIAL, serialNumber);
     try (CloseableHttpResponse response = httpClient.execute(httpGet)) {
       //v3已经改为通过状态码判断200 204 成功
       int statusCode = response.getStatusLine().getStatusCode();
@@ -298,6 +307,8 @@ public class WxPayServiceApacheHttpImpl extends BaseWxPayServiceImpl {
     httpPut.setEntity(entity);
     httpPut.addHeader(ACCEPT, APPLICATION_JSON);
     httpPut.addHeader(CONTENT_TYPE, APPLICATION_JSON);
+    String serialNumber = getWechatpaySerial(getConfig());
+    httpPut.addHeader(WECHATPAY_SERIAL, serialNumber);
     return requestV3(url, httpPut);
   }
 
@@ -306,6 +317,8 @@ public class WxPayServiceApacheHttpImpl extends BaseWxPayServiceImpl {
     HttpDelete httpDelete = new HttpDelete(url);
     httpDelete.addHeader(ACCEPT, APPLICATION_JSON);
     httpDelete.addHeader(CONTENT_TYPE, APPLICATION_JSON);
+    String serialNumber = getWechatpaySerial(getConfig());
+    httpDelete.addHeader(WECHATPAY_SERIAL, serialNumber);
     return requestV3(url, httpDelete);
   }