diff --git a/BBWYB.Server.API/Controllers/PurchaseSchemeController.cs b/BBWYB.Server.API/Controllers/PurchaseSchemeController.cs
index 171612f..1b7f63d 100644
--- a/BBWYB.Server.API/Controllers/PurchaseSchemeController.cs
+++ b/BBWYB.Server.API/Controllers/PurchaseSchemeController.cs
@@ -172,9 +172,19 @@ namespace BBWYB.Server.API.Controllers
         /// <param name="request"></param>
         /// <returns>最新的采购方案成本</returns>
         [HttpDelete]
-        public decimal DeletePurchaseSku([FromBody]DeletePurchaseSkuRequest request)
-        { 
+        public decimal DeletePurchaseSku([FromBody] DeletePurchaseSkuRequest request)
+        {
             return purchaseSchemeBusiness.DeletePurchaseSku(request);
         }
+
+        /// <summary>
+        /// 设置首选采购方案,同时互斥相同Sku的其他采购方案
+        /// </summary>
+        /// <param name="schemeId"></param>
+        [HttpPost("{schemeId}")]
+        public void SetFirstPurchaseScheme([FromRoute]long schemeId)
+        {
+            purchaseSchemeBusiness.SetFirstPurchaseScheme(schemeId);
+        }
     }
 }
diff --git a/BBWYB.Server.Business/PurchaseScheme/PurchaseSchemeBusiness.cs b/BBWYB.Server.Business/PurchaseScheme/PurchaseSchemeBusiness.cs
index 4da9300..f3ffbde 100644
--- a/BBWYB.Server.Business/PurchaseScheme/PurchaseSchemeBusiness.cs
+++ b/BBWYB.Server.Business/PurchaseScheme/PurchaseSchemeBusiness.cs
@@ -639,7 +639,7 @@ namespace BBWYB.Server.Business
                                                 .Where((psp, p) => psp.SkuPurchaseSchemeId == ps.Id).Any());
             }
             //var sql = select.ToSql();
-            var purchaseSchemeList = select.OrderByDescending(ps => ps.CreateTime).ToList<PurchaseSchemeResponse>();
+            var purchaseSchemeList = select.OrderByDescending(ps => ps.IsFirst).OrderByDescending(ps => ps.CreateTime).ToList<PurchaseSchemeResponse>();
 
 
             if (purchaseSchemeList.Count > 0)
@@ -1194,5 +1194,25 @@ namespace BBWYB.Server.Business
             });
             return defaultCost;
         }
+
+        /// <summary>
+        /// 设置首选采购方案
+        /// </summary>
+        /// <param name="schemeId"></param>
+        public void SetFirstPurchaseScheme(long schemeId)
+        {
+            var scheme = fsql.Select<PurchaseScheme>(schemeId).ToOne(s => new
+            {
+                s.Id,
+                s.SkuId
+            });
+            if (scheme == null)
+                new BusinessException("采购方案不存在");
+            fsql.Transaction(() =>
+            {
+                fsql.Update<PurchaseScheme>().Set(s => s.IsFirst, 0).Where(s => s.SkuId == scheme.SkuId && s.Id != schemeId).ExecuteAffrows();
+                fsql.Update<PurchaseScheme>(schemeId).Set(s => s.IsFirst, 1).ExecuteAffrows();
+            });
+        }
     }
 }
diff --git a/BBWYB.Server.Model/Db/PurchaseScheme/PurchaseScheme.cs b/BBWYB.Server.Model/Db/PurchaseScheme/PurchaseScheme.cs
index b46941e..a840856 100644
--- a/BBWYB.Server.Model/Db/PurchaseScheme/PurchaseScheme.cs
+++ b/BBWYB.Server.Model/Db/PurchaseScheme/PurchaseScheme.cs
@@ -93,6 +93,11 @@ namespace BBWYB.Server.Model
         /// 采购金额
         /// </summary>
         public decimal? PurchasedAmount { get; set; } = 0M;
+
+        /// <summary>
+        /// 首选采购方案 (是=1 否=0)
+        /// </summary>
+        public int? IsFirst { get; set; } = 0;
     }
 
 }