diff --git a/PythonProject/model/all_model.py b/PythonProject/model/all_model.py
index 4c96f84..91e93f7 100644
--- a/PythonProject/model/all_model.py
+++ b/PythonProject/model/all_model.py
@@ -11,7 +11,7 @@ class Student_Model(Base):
                     ,comment='学生编号')
 
     class_id = Column(Integer
-                    ,ForeignKey('wl_class.class_id')
+                    ,ForeignKey('wl_class.class_id', ondelete='CASCADE')
                     ,comment='班级编号'
                     )