diff --git a/Service/DeviceService.cs b/Service/DeviceService.cs
index 9ed09f8..dbb42bc 100644
--- a/Service/DeviceService.cs
+++ b/Service/DeviceService.cs
@@ -64,6 +64,15 @@ namespace LY.App.Service
         public async Task<ApiResult> Add(AddDevice input)
         {
             var entity = input.Adapt<DeviceEntity>();
+            var exists = await _db.Queryable<DeviceEntity>().FirstAsync(s => s.DeviceSN == entity.DeviceSN);
+            if (exists!= null)
+            {
+                return new ApiResult()
+                {
+                    code = 1,
+                    msg = "设备SN已存在"
+                };
+            }
             var id = await _db.Insertable(entity).ExecuteReturnSnowflakeIdAsync();
             entity.Id = id;
             await AddDevice2Manager(entity);