diff --git a/erp/erp.go b/erp/erp.go
index 222bbc5..66070be 100644
--- a/erp/erp.go
+++ b/erp/erp.go
@@ -13,6 +13,7 @@ type Erp struct {
 	Template         template
 	Accounting       accounting
 	Payable          payable
+	Payment          payment
 	Receivable       receivable
 	Receipt          receipt
 	Expense          expense
diff --git a/ik3cloud/constant/constant.go b/ik3cloud/constant/constant.go
index ad09c0e..c8c8cd0 100644
--- a/ik3cloud/constant/constant.go
+++ b/ik3cloud/constant/constant.go
@@ -79,6 +79,14 @@ const (
 	PaymentTypeRequest  PaymentType = "FKDLX11_SYS" // 报销付款单
 )
 
+type PaymentPurpose = string
+
+const (
+	PaymentPurposePurchase PaymentPurpose = "SFKYT08_SYS" // 采购付款单
+	PaymentPurposeExpense  PaymentPurpose = "SFKYT009"    // 费用报销
+	PaymentPurposeOther    PaymentPurpose = "SFKYT12_SYS" // 其他支出
+)
+
 type ReceiptType = string
 
 const (
diff --git a/ik3cloud/payment.go b/ik3cloud/payment.go
index e69080e..90415b8 100644
--- a/ik3cloud/payment.go
+++ b/ik3cloud/payment.go
@@ -32,8 +32,8 @@ type PaymentCostItem struct {
 	InvoiceSerial    string          // 发票号
 	DepartmentNumber string          // 核算部门
 	//SettlementMethod string          // 结算方式
-	//PaymentPurpose   string          // 付款用途
-	ExpenseItem string // 费用项目
+	PaymentPurpose constant.PaymentPurpose // 付款用途
+	ExpenseItem    string                  // 费用项目
 }
 
 // Save @TITLE 保存付款单