diff --git a/src/Oms.Application/Services/Channels/SalesProductService.Helpers.cs b/src/Oms.Application/Services/Channels/SalesProductService.Helpers.cs
index 344f1ab..5cf568d 100644
--- a/src/Oms.Application/Services/Channels/SalesProductService.Helpers.cs
+++ b/src/Oms.Application/Services/Channels/SalesProductService.Helpers.cs
@@ -388,10 +388,11 @@ public partial class SalesProductService
         };
 
     /// <summary>
-    /// 保险/偏远费等附加费用项的计费条件校验。
+    /// 保险/偏远费等附加费用项的计费条件校验；同一提交批次内费用项不可重复。
     /// </summary>
     private static void ValidateBillingPriceItemRules(IReadOnlyList<SalesProductPriceSaveInput> prices)
     {
+        EnsureUniqueCostItemsInBatch(prices.Select(x => x.CostItem));
         foreach (var price in prices)
         {
             var costItem = price.CostItem?.Trim() ?? string.Empty;
@@ -417,6 +418,44 @@ public partial class SalesProductService
         }
     }
 
+    /// <summary>
+    /// 同一销售产品下每种费用项只能有一条卖价配置。
+    /// </summary>
+    private async Task EnsureCostItemUniqueAsync(int salesProductId, string? costItem, int? excludePriceId)
+    {
+        var trimmed = costItem?.Trim() ?? string.Empty;
+        if (string.IsNullOrWhiteSpace(trimmed))
+        {
+            throw new Fake.Application.BusinessException("费用项不能为空");
+        }
+
+        var existing = await SalesProductRepository.GetPricesAsync(salesProductId);
+        var duplicated = existing.Any(p =>
+            (!excludePriceId.HasValue || p.Id != excludePriceId.Value)
+            && string.Equals(p.CostItem?.Trim(), trimmed, StringComparison.OrdinalIgnoreCase));
+        if (duplicated)
+        {
+            throw new Fake.Application.BusinessException(
+                $"该产品已存在费用项「{trimmed}」，同一产品下每种费用项只能有一条");
+        }
+    }
+
+    private static void EnsureUniqueCostItemsInBatch(IEnumerable<string?> costItems)
+    {
+        var duplicates = costItems
+            .Select(x => x?.Trim() ?? string.Empty)
+            .Where(x => !string.IsNullOrWhiteSpace(x))
+            .GroupBy(x => x, StringComparer.OrdinalIgnoreCase)
+            .Where(g => g.Count() > 1)
+            .Select(g => g.Key)
+            .ToList();
+        if (duplicates.Count > 0)
+        {
+            throw new Fake.Application.BusinessException(
+                $"同一产品下费用项不能重复：{string.Join("、", duplicates)}");
+        }
+    }
+
     private static string? NormalizeAdditionalServices(string? raw)
     {
         if (string.IsNullOrWhiteSpace(raw))
diff --git a/src/Oms.Application/Services/Channels/SalesProductService.cs b/src/Oms.Application/Services/Channels/SalesProductService.cs
index 3b86f15..29ddaf2 100644
--- a/src/Oms.Application/Services/Channels/SalesProductService.cs
+++ b/src/Oms.Application/Services/Channels/SalesProductService.cs
@@ -159,6 +159,7 @@ public partial class SalesProductService : ApplicationService
     {
         await GetProductOrThrowAsync(input.SalesProductId);
         ValidateBillingPriceItemRules([input]);
+        await EnsureCostItemUniqueAsync(input.SalesProductId, input.CostItem, excludePriceId: null);
         await SalesProductRepository.InsertPriceAsync(
             new SalesProductPrice
             {
@@ -190,6 +191,7 @@ public partial class SalesProductService : ApplicationService
         }
 
         ValidateBillingPriceItemRules([input]);
+        await EnsureCostItemUniqueAsync(input.SalesProductId, input.CostItem, excludePriceId: price.Id);
         price.SerialNumber = input.SerialNumber;
         price.Status = input.Status;
         price.PriceName = input.PriceName;
diff --git a/src/Oms.Application/Services/Channels/ServiceChannelService.Helpers.cs b/src/Oms.Application/Services/Channels/ServiceChannelService.Helpers.cs
index 2a00598..0f8c182 100644
--- a/src/Oms.Application/Services/Channels/ServiceChannelService.Helpers.cs
+++ b/src/Oms.Application/Services/Channels/ServiceChannelService.Helpers.cs
@@ -329,10 +329,11 @@ public partial class ServiceChannelService
     }
 
     /// <summary>
-    /// 买价偏远费等附加费用项的计费条件校验。
+    /// 买价偏远费等附加费用项的计费条件校验；同一提交批次内费用项不可重复。
     /// </summary>
     private static void ValidateBillingPriceItemRules(IReadOnlyList<ServiceChannelPriceSaveInput> prices)
     {
+        EnsureUniqueCostItemsInBatch(prices.Select(x => x.CostItem));
         foreach (var price in prices)
         {
             var costItem = price.CostItem?.Trim() ?? string.Empty;
@@ -349,6 +350,44 @@ public partial class ServiceChannelService
         }
     }
 
+    /// <summary>
+    /// 同一服务渠道下每种费用项只能有一条买价配置。
+    /// </summary>
+    private async Task EnsureCostItemUniqueAsync(int serviceChannelId, string? costItem, int? excludePriceId)
+    {
+        var trimmed = costItem?.Trim() ?? string.Empty;
+        if (string.IsNullOrWhiteSpace(trimmed))
+        {
+            throw new Fake.Application.BusinessException("费用项不能为空");
+        }
+
+        var existing = await ServiceChannelRepository.GetPricesAsync(serviceChannelId);
+        var duplicated = existing.Any(p =>
+            (!excludePriceId.HasValue || p.Id != excludePriceId.Value)
+            && string.Equals(p.CostItem?.Trim(), trimmed, StringComparison.OrdinalIgnoreCase));
+        if (duplicated)
+        {
+            throw new Fake.Application.BusinessException(
+                $"该渠道已存在费用项「{trimmed}」，同一渠道下每种费用项只能有一条");
+        }
+    }
+
+    private static void EnsureUniqueCostItemsInBatch(IEnumerable<string?> costItems)
+    {
+        var duplicates = costItems
+            .Select(x => x?.Trim() ?? string.Empty)
+            .Where(x => !string.IsNullOrWhiteSpace(x))
+            .GroupBy(x => x, StringComparer.OrdinalIgnoreCase)
+            .Where(g => g.Count() > 1)
+            .Select(g => g.Key)
+            .ToList();
+        if (duplicates.Count > 0)
+        {
+            throw new Fake.Application.BusinessException(
+                $"同一渠道下费用项不能重复：{string.Join("、", duplicates)}");
+        }
+    }
+
     private static ServiceChannelGroupListOutput MapGroupListOutput(ServiceChannelGroup entity)
     {
         return new ServiceChannelGroupListOutput
diff --git a/src/Oms.Application/Services/Channels/ServiceChannelService.cs b/src/Oms.Application/Services/Channels/ServiceChannelService.cs
index 7188468..137cd20 100644
--- a/src/Oms.Application/Services/Channels/ServiceChannelService.cs
+++ b/src/Oms.Application/Services/Channels/ServiceChannelService.cs
@@ -223,6 +223,7 @@ public partial class ServiceChannelService : ApplicationService
     {
         await GetEntityOrThrowAsync(input.ServiceChannelId);
         ValidateBillingPriceItemRules([input]);
+        await EnsureCostItemUniqueAsync(input.ServiceChannelId, input.CostItem, excludePriceId: null);
         await ServiceChannelRepository.InsertPriceAsync(
             new ServiceChannelPrice
             {
@@ -254,6 +255,7 @@ public partial class ServiceChannelService : ApplicationService
         }
 
         ValidateBillingPriceItemRules([input]);
+        await EnsureCostItemUniqueAsync(input.ServiceChannelId, input.CostItem, excludePriceId: price.Id);
         price.SerialNumber = input.SerialNumber;
         price.Status = input.Status;
         price.PriceName = input.PriceName;