diff --git a/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/APPPayRequest.java b/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/APPPayRequest.java
index 7efb1a6a..69a8d174 100644
--- a/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/APPPayRequest.java
+++ b/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/APPPayRequest.java
@@ -2,6 +2,7 @@ package com.foxinmy.weixin4j.payment.mch;
 
 import com.foxinmy.weixin4j.model.WeixinPayAccount;
 import com.foxinmy.weixin4j.payment.PayRequest;
+import com.foxinmy.weixin4j.type.TradeType;
 import com.foxinmy.weixin4j.util.DigestUtil;
 import com.foxinmy.weixin4j.util.MapUtil;
 
@@ -23,6 +24,11 @@ public class APPPayRequest extends AbstractPayRequest {
 		super(prePayId, payAccount);
 	}
 
+	@Override
+	public TradeType getTradeType() {
+		return TradeType.APP;
+	}
+
 	/**
 	 * <font color="red">只做查看之用,请不要尝试作为支付请求</font>
 	 */
diff --git a/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/JSAPIPayRequest.java b/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/JSAPIPayRequest.java
index 62655b66..c570d17b 100644
--- a/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/JSAPIPayRequest.java
+++ b/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/JSAPIPayRequest.java
@@ -4,6 +4,7 @@ import com.alibaba.fastjson.JSON;
 import com.foxinmy.weixin4j.model.WeixinPayAccount;
 import com.foxinmy.weixin4j.payment.PayRequest;
 import com.foxinmy.weixin4j.type.SignType;
+import com.foxinmy.weixin4j.type.TradeType;
 import com.foxinmy.weixin4j.util.DigestUtil;
 
 /**
@@ -28,6 +29,11 @@ public class JSAPIPayRequest extends AbstractPayRequest {
 	public JSAPIPayRequest(String prePayId, WeixinPayAccount payAccount) {
 		super(prePayId, payAccount);
 	}
+	
+	@Override
+	public TradeType getTradeType() {
+		return TradeType.JSAPI;
+	}
 
 	@Override
 	public PayRequest toRequestObject() {
diff --git a/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/MchPayRequest.java b/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/MchPayRequest.java
index 2d0240ff..385911a9 100644
--- a/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/MchPayRequest.java
+++ b/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/MchPayRequest.java
@@ -2,6 +2,7 @@ package com.foxinmy.weixin4j.payment.mch;
 
 import com.foxinmy.weixin4j.model.WeixinPayAccount;
 import com.foxinmy.weixin4j.payment.PayRequest;
+import com.foxinmy.weixin4j.type.TradeType;
 
 /**
  * 支付请求接口
@@ -9,7 +10,7 @@ import com.foxinmy.weixin4j.payment.PayRequest;
  * @className MchPayRequest
  * @author jy
  * @date 2015年12月25日
- * @since JDK 1.7
+ * @since JDK 1.6
  * @see JSAPIPayRequest JS支付
  * @see NATIVEPayRequest 扫码支付
  * @see APPPayRequest APP支付
@@ -30,6 +31,13 @@ public interface MchPayRequest {
 	 */
 	public WeixinPayAccount getPayAccount();
 
+	/**
+	 * 交易类型
+	 * 
+	 * @return
+	 */
+	public TradeType getTradeType();
+
 	/**
 	 * 支付请求字符串
 	 * 
diff --git a/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/NATIVEPayRequest.java b/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/NATIVEPayRequest.java
index 38180120..54b992a7 100644
--- a/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/NATIVEPayRequest.java
+++ b/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/NATIVEPayRequest.java
@@ -2,6 +2,7 @@ package com.foxinmy.weixin4j.payment.mch;
 
 import com.foxinmy.weixin4j.model.WeixinPayAccount;
 import com.foxinmy.weixin4j.payment.PayRequest;
+import com.foxinmy.weixin4j.type.TradeType;
 
 /**
  * NATIVE扫码支付(模式二)
@@ -25,6 +26,11 @@ public class NATIVEPayRequest extends AbstractPayRequest {
 		this.codeUrl = codeUrl;
 	}
 
+	@Override
+	public TradeType getTradeType() {
+		return TradeType.NATIVE;
+	}
+
 	/**
 	 * <font color="red">只做查看之用,请不要尝试作为支付请求</font>
 	 */
diff --git a/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/WAPPayRequest.java b/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/WAPPayRequest.java
index 99b9538b..1a7514fe 100644
--- a/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/WAPPayRequest.java
+++ b/weixin4j-base/src/main/java/com/foxinmy/weixin4j/payment/mch/WAPPayRequest.java
@@ -4,6 +4,7 @@ import com.foxinmy.weixin4j.model.Consts;
 import com.foxinmy.weixin4j.model.WeixinPayAccount;
 import com.foxinmy.weixin4j.payment.PayRequest;
 import com.foxinmy.weixin4j.payment.PayURLConsts;
+import com.foxinmy.weixin4j.type.TradeType;
 import com.foxinmy.weixin4j.util.DigestUtil;
 import com.foxinmy.weixin4j.util.MapUtil;
 import com.foxinmy.weixin4j.util.URLEncodingUtil;
@@ -26,12 +27,18 @@ public class WAPPayRequest extends AbstractPayRequest {
 		super(prePayId, payAccount);
 	}
 
+	@Override
+	public TradeType getTradeType() {
+		return TradeType.WAP;
+	}
+
 	/**
 	 * <font color="red">只做查看之用,请不要尝试作为支付请求</font>
 	 */
 	@Override
 	public PayRequest toRequestObject() {
-		PayRequest payRequest = new PayRequest(getPayAccount().getId(), "WAP");
+		PayRequest payRequest = new PayRequest(getPayAccount().getId(),
+				getTradeType().name());
 		payRequest.setPrepayId(getPrePayId());
 		return payRequest;
 	}