diff --git a/backend/services/planting-service/src/pre-planting/application/services/pre-planting-application.service.ts b/backend/services/planting-service/src/pre-planting/application/services/pre-planting-application.service.ts
index feaf5773..79876c32 100644
--- a/backend/services/planting-service/src/pre-planting/application/services/pre-planting-application.service.ts
+++ b/backend/services/planting-service/src/pre-planting/application/services/pre-planting-application.service.ts
@@ -417,7 +417,7 @@ export class PrePlantingApplicationService {
       where: { orderNo: { in: merge.sourceOrderNos } },
       select: { totalAmount: true },
     });
-    const greenPointsAmount = sourceOrders.reduce((sum, o) => sum + o.totalAmount, 0);
+    const greenPointsAmount = sourceOrders.reduce((sum, o) => sum + Number(o.totalAmount), 0);
     const totalAmount = Math.round(greenPointsAmount * 1.1 * 100) / 100; // 含税 CNY
 
     // 生成北京时间日期