diff --git a/IRaCIS.Core.Domain/Reading/ReadingCriterion/ReadingQuestionCriterionTrial.cs b/IRaCIS.Core.Domain/Reading/ReadingCriterion/ReadingQuestionCriterionTrial.cs
index e1bc0a2af..d27815e83 100644
--- a/IRaCIS.Core.Domain/Reading/ReadingCriterion/ReadingQuestionCriterionTrial.cs
+++ b/IRaCIS.Core.Domain/Reading/ReadingCriterion/ReadingQuestionCriterionTrial.cs
@@ -190,7 +190,7 @@ public class ReadingQuestionCriterionTrial : BaseAddAuditEntity
     /// 默认SegmentName
     /// </summary>
     [MaxLength]
-    public DefaultSegmentNameDto DefaultSegmentName { get; set; }
+    public DefaultSegmentNameDto DefaultSegmentName { get; set; } = new DefaultSegmentNameDto();
 }