diff --git a/IRaCIS.Core.Application/Service/Reading/ReadingCriterion/ReadingQuestionService.cs b/IRaCIS.Core.Application/Service/Reading/ReadingCriterion/ReadingQuestionService.cs
index a53094fa6..5bb8ff5c3 100644
--- a/IRaCIS.Core.Application/Service/Reading/ReadingCriterion/ReadingQuestionService.cs
+++ b/IRaCIS.Core.Application/Service/Reading/ReadingCriterion/ReadingQuestionService.cs
@@ -56,6 +56,16 @@ namespace IRaCIS.Core.Application.Service
         [HttpPost]
         public async Task<bool> SetTrialQuestionExportResult(SetTrialQuestionExportResultInDto inDto)
         {
+
+            var cDISCCodeList = inDto.QuestionList.Where(x => x.CDISCCode.IsNotNullOrEmpty()).Select(x => x.CDISCCode).ToList();
+
+            cDISCCodeList.AddRange(inDto.TableQuestionList.Where(x => x.CDISCCode.IsNotNullOrEmpty()).Select(x => x.CDISCCode).ToList());
+
+            if (cDISCCodeList.Distinct().Count() != cDISCCodeList.Count)
+            {
+                throw new BusinessValidationFailedException(_localizer["ReadingQuestion_CDISCCodeRepeat"]);
+            }
+
             List<ExportResult> needAdd = new List<ExportResult>()
             {
                 ExportResult.DetailedTableOfAdjudicationResults,