diff --git a/IntegrationGuide.md b/IntegrationGuide.md
index 9c999f0..6d2c1f3 100644
--- a/IntegrationGuide.md
+++ b/IntegrationGuide.md
@@ -169,7 +169,17 @@ InitializeCallback为初始化回调接口,此接口只有一个回调方法init
 调用pay方法时,必须穿入一个bundle对象,包含如上字段,除nick和roleId外所有字段必须全部包含,其中sessionKey为登录时返回的sessionKey  
     
     
-2)PurchaseCallback为支付状态回调接口,此接口含有3个方法  
+2)IAP支付，roleId为可选参数，其他参数必传   
+    
+    Bundle payInfo = new Bundle();
+    payInfo.putString("product", "gp_skuId");
+    payInfo.putFloat("amount", 0.1f);
+    payInfo.putString("extraInfo", "This is demo!");
+    payInfo.putString("serverId", "100");
+    payInfo.putString("roleId","100123");
+    GumpSDK.iap(MainActivity.this, payInfo, PurchaseCallback);
+                
+3)PurchaseCallback为支付状态回调接口,此接口含有3个方法  
 
     @Override
     public void onPurchaseCompleted(PurchaseResult result) {