diff --git a/IRaCIS.Core.Application/Service/Common/ExcelExportService.cs b/IRaCIS.Core.Application/Service/Common/ExcelExportService.cs
index 6382d549..6732e954 100644
--- a/IRaCIS.Core.Application/Service/Common/ExcelExportService.cs
+++ b/IRaCIS.Core.Application/Service/Common/ExcelExportService.cs
@@ -526,7 +526,7 @@ namespace IRaCIS.Core.Application.Service.Common
                 item.AgainEvaluateResult = selfAnalysisTask?.EvaluateResult ?? String.Empty;
 
                 //将自身一致性分析的字段 赋值到访视任务这个字段
-                item.IsAnalysisDiffToOriginalData = selfAnalysisTask.IsAnalysisDiffToOriginalData;
+                item.IsAnalysisDiffToOriginalData = selfAnalysisTask?.IsAnalysisDiffToOriginalData;
 
             }