diff --git a/apps/wpm/views.py b/apps/wpm/views.py
index 64469d64..1827d5b3 100644
--- a/apps/wpm/views.py
+++ b/apps/wpm/views.py
@@ -801,9 +801,9 @@ class MlogbwViewSet(CustomModelViewSet):
             raise ParseError("不能删除该产出明细")
         
         ftest = instance.ftest
+        instance.delete()
         if ftest:
             ftest.delete()
-        instance.delete()
         Mlogbw.cal_count_notok(mlogb)
 
         # 如果是输入且输出追踪到个，需同步删除