diff --git a/VOL.Business/Services/HomeWork/S_HomeWorkService.cs b/VOL.Business/Services/HomeWork/S_HomeWorkService.cs
index 8a4e32f..bfe24b7 100644
--- a/VOL.Business/Services/HomeWork/S_HomeWorkService.cs
+++ b/VOL.Business/Services/HomeWork/S_HomeWorkService.cs
@@ -141,7 +141,7 @@ namespace VOL.Business.Services.Norm
             if (paramDto.EndTime.HasValue)
             {
                 DateTime detectionDate = paramDto.EndTime.Value.Date;
-                query = query.Where(x => x.EndTime.HasValue && x.EndTime.Value.Date <= detectionDate);
+                query = query.Where(x => x.StartTime.HasValue && x.StartTime.Value.Date <= detectionDate);
             }
 
             res.Total = await query.CountAsync();