diff --git a/workflow-engine-core/src/main/java/cn/axzo/workflow/core/service/impl/BpmnProcessInstanceServiceImpl.java b/workflow-engine-core/src/main/java/cn/axzo/workflow/core/service/impl/BpmnProcessInstanceServiceImpl.java
index e3864d038..4dc5eaf92 100644
--- a/workflow-engine-core/src/main/java/cn/axzo/workflow/core/service/impl/BpmnProcessInstanceServiceImpl.java
+++ b/workflow-engine-core/src/main/java/cn/axzo/workflow/core/service/impl/BpmnProcessInstanceServiceImpl.java
@@ -1289,7 +1289,9 @@ public class BpmnProcessInstanceServiceImpl implements BpmnProcessInstanceServic
                 processingTask.ifPresent(i -> {
                     List<BpmnTaskDelegateAssigner> assigners = new ArrayList<>(ListUtils.emptyIfNull(i.getForecastAssignees()));
                     if(CollectionUtils.isEmpty(assigners)) {
-                        assigners.add(i.getAssigneeSnapshot());
+                        if(Objects.nonNull(i.getAssigneeSnapshot())) {
+                            assigners.add(i.getAssigneeSnapshot());
+                        }
                     }
                     assigners.add(BpmnTaskDelegateAssigner.toObjectCompatible(CollectionUtils.isEmpty(ListUtils.emptyIfNull(e.getAssigneeFull())) ? null : e.getAssigneeFull().get(0)));
                     switch (i.getNodeMode()) {