diff --git a/workflow-engine-core/src/main/java/cn/axzo/workflow/core/engine/cmd/CustomCompleteDummyTaskCmd.java b/workflow-engine-core/src/main/java/cn/axzo/workflow/core/engine/cmd/CustomCompleteDummyTaskCmd.java
index 67f73de8d..6a9f920af 100644
--- a/workflow-engine-core/src/main/java/cn/axzo/workflow/core/engine/cmd/CustomCompleteDummyTaskCmd.java
+++ b/workflow-engine-core/src/main/java/cn/axzo/workflow/core/engine/cmd/CustomCompleteDummyTaskCmd.java
@@ -62,9 +62,11 @@ public class CustomCompleteDummyTaskCmd implements Command<Void>, Serializable {
             taskService.saveTask(task);
         }
 
-        Authentication.setAuthenticatedUserId("system");
-        CustomTaskHelper.addComment(commandContext, task, COMMENT_TYPE_OPERATION_DESC, operationDesc);
-        Authentication.setAuthenticatedUserId(null);
+        if (StringUtils.hasText(operationDesc)) {
+            Authentication.setAuthenticatedUserId("system");
+            CustomTaskHelper.addComment(commandContext, task, COMMENT_TYPE_OPERATION_DESC, operationDesc);
+            Authentication.setAuthenticatedUserId(null);
+        }
 
         taskService.complete(task.getId());
 
diff --git a/workflow-engine-core/src/main/java/cn/axzo/workflow/core/service/impl/BpmnProcessTaskServiceImpl.java b/workflow-engine-core/src/main/java/cn/axzo/workflow/core/service/impl/BpmnProcessTaskServiceImpl.java
index 80f16290c..6c1224225 100644
--- a/workflow-engine-core/src/main/java/cn/axzo/workflow/core/service/impl/BpmnProcessTaskServiceImpl.java
+++ b/workflow-engine-core/src/main/java/cn/axzo/workflow/core/service/impl/BpmnProcessTaskServiceImpl.java
@@ -645,7 +645,8 @@ public class BpmnProcessTaskServiceImpl implements BpmnProcessTaskService {
         CommandExecutor commandExecutor = processEngineConfiguration.getCommandExecutor();
         commandExecutor.execute(new CustomCompleteDummyTaskCmd(dto.getProcessInstanceId(), dto.getTaskId(),
                 Objects.isNull(dto.getRobotNode()) ? null : dto.getRobotNode().getFlowNodeName(),
-                dto.getRobotNode().getOperationDesc(), extAxHiTaskInstService));
+                Objects.isNull(dto.getRobotNode()) ? null : dto.getRobotNode().getOperationDesc(),
+                extAxHiTaskInstService));
     }
 
     @Override