diff --git a/workflow-engine-core/src/main/java/cn/axzo/workflow/core/engine/behavior/CustomServiceTaskDelegateExpressionActivityBehavior.java b/workflow-engine-core/src/main/java/cn/axzo/workflow/core/engine/behavior/CustomServiceTaskDelegateExpressionActivityBehavior.java
index 2b9c306df..8af0b540f 100644
--- a/workflow-engine-core/src/main/java/cn/axzo/workflow/core/engine/behavior/CustomServiceTaskDelegateExpressionActivityBehavior.java
+++ b/workflow-engine-core/src/main/java/cn/axzo/workflow/core/engine/behavior/CustomServiceTaskDelegateExpressionActivityBehavior.java
@@ -90,6 +90,8 @@ public class CustomServiceTaskDelegateExpressionActivityBehavior extends Service
             eventDispatcher.dispatchEvent(new ExtTaskInstUpdateEvent(execution.getProcessInstanceId(),
                     execution.getCurrentActivityId(), serviceTask.getId(), APPROVED),
                 processEngineConfiguration.getEngineCfgKey());
+
+            taskService.complete(serviceTask.getId());
         } else {
             log.warn("ServiceTask is null, executionId: {}, activityId: {}", execution.getId(),
                 execution.getCurrentActivityId());