diff --git a/backend/ai_services/services.py b/backend/ai_services/services.py
index 3e1ab81..0ceca94 100644
--- a/backend/ai_services/services.py
+++ b/backend/ai_services/services.py
@@ -323,14 +323,30 @@ class AliyunTingwuService:
 
         # 4. 自动触发 AI 评估 (如果任务首次成功且有启用的模板)
         if previous_status != 'SUCCEEDED' and task.status == 'SUCCEEDED' and task.transcription:
-            # 同样改为异步触发
+            # 同样改为异步触发，传递 task.id 以避免线程中的对象状态问题
             import threading
-            threading.Thread(target=self.trigger_ai_evaluations, args=(task,)).start()
+            threading.Thread(target=self.trigger_ai_evaluations, args=(task.id,)).start()
 
-    def trigger_ai_evaluations(self, task):
+    def trigger_ai_evaluations(self, task_id):
         """
         根据启用的模板自动触发 AI 评估
         """
+        try:
+            # 在线程中重新获取 task 对象，并预加载 project，避免懒加载导致的线程数据库连接问题
+            from .models import TranscriptionTask
+            task = TranscriptionTask.objects.select_related('project').get(id=task_id)
+        except Exception as e:
+            # 兼容处理：如果 task_id 其实是 task 对象（虽然我们上面改了，但防止其他地方调用传错）
+            if hasattr(task_id, 'id'):
+                try:
+                    from .models import TranscriptionTask
+                    task = TranscriptionTask.objects.select_related('project').get(id=task_id.id)
+                except:
+                    task = task_id
+            else:
+                logger.error(f"Failed to retrieve task {task_id}: {e}")
+                return
+
         active_templates = AIEvaluationTemplate.objects.filter(is_active=True)
         if not active_templates.exists():
             logger.info("No active AI evaluation templates found.")
@@ -340,6 +356,11 @@ class AliyunTingwuService:
         service = BailianService()
 
         for template in active_templates:
+            # 检查是否已经存在相同的评估，避免重复创建
+            if AIEvaluation.objects.filter(task=task, template=template).exists():
+                logger.info(f"Evaluation for task {task.id} and template {template.name} already exists.")
+                continue
+
             # 创建评估记录
             evaluation = AIEvaluation.objects.create(
                 task=task,
@@ -349,8 +370,7 @@ class AliyunTingwuService:
                 status=AIEvaluation.Status.PENDING
             )
             
-            # 触发评估 (同步执行，或者放入 Celery 任务)
-            # 这里为了简单直接调用，生产环境建议使用 Celery
+            # 触发评估
             try:
                 service.evaluate_task(evaluation)
                 logger.info(f"Triggered evaluation {evaluation.id} for template {template.name}")
diff --git a/backend/ai_services/views.py b/backend/ai_services/views.py
index a0103e9..357fa86 100644
--- a/backend/ai_services/views.py
+++ b/backend/ai_services/views.py
@@ -116,6 +116,7 @@ class TranscriptionTaskViewSet(viewsets.ModelViewSet):
                     pass # Ignore invalid project_id
 
             task_record = TranscriptionTask.objects.create(**task_data)
+            logger.info(f"Created TranscriptionTask {task_record.id} with project_id={project_id}")
 
             # 3. 调用听悟接口创建任务
             try: