diff --git a/skywalking-commons/skywalking-trace/src/main/java/com/a/eye/skywalking/trace/TraceSegment.java b/skywalking-commons/skywalking-trace/src/main/java/com/a/eye/skywalking/trace/TraceSegment.java
index 56b1727d17d18844c2ed9841779bf9e425806812..b83385930275bbe43fd5c89433493bd943d58433 100644
--- a/skywalking-commons/skywalking-trace/src/main/java/com/a/eye/skywalking/trace/TraceSegment.java
+++ b/skywalking-commons/skywalking-trace/src/main/java/com/a/eye/skywalking/trace/TraceSegment.java
@@ -158,6 +158,9 @@ public class TraceSegment implements ISerializable<SegmentMessage> {
     }
 
     public List<TraceSegmentRef> getRefs() {
+        if(refs == null){
+            return null;
+        }
         return Collections.unmodifiableList(refs);
     }