diff --git a/backend/app/admin/model/sys_role_menu.py b/backend/app/admin/model/m2m.py
similarity index 57%
rename from backend/app/admin/model/sys_role_menu.py
rename to backend/app/admin/model/m2m.py
index e1f2cb7d..31040390 100644
--- a/backend/app/admin/model/sys_role_menu.py
+++ b/backend/app/admin/model/m2m.py
@@ -4,6 +4,14 @@
 
 from backend.common.model import MappedBase
 
+sys_user_role = Table(
+    'sys_user_role',
+    MappedBase.metadata,
+    Column('id', INT, primary_key=True, unique=True, index=True, autoincrement=True, comment='主键ID'),
+    Column('user_id', Integer, ForeignKey('sys_user.id', ondelete='CASCADE'), primary_key=True, comment='用户ID'),
+    Column('role_id', Integer, ForeignKey('sys_role.id', ondelete='CASCADE'), primary_key=True, comment='角色ID'),
+)
+
 sys_role_menu = Table(
     'sys_role_menu',
     MappedBase.metadata,
diff --git a/backend/app/admin/model/sys_dept.py b/backend/app/admin/model/sys_dept.py
index 2e1492e9..a85805d9 100644
--- a/backend/app/admin/model/sys_dept.py
+++ b/backend/app/admin/model/sys_dept.py
@@ -22,11 +22,13 @@ class Dept(Base):
     email: Mapped[str | None] = mapped_column(String(50), default=None, comment='邮箱')
     status: Mapped[int] = mapped_column(default=1, comment='部门状态(0停用 1正常)')
     del_flag: Mapped[bool] = mapped_column(default=False, comment='删除标志（0删除 1存在）')
+
     # 父级部门一对多
     parent_id: Mapped[int | None] = mapped_column(
         ForeignKey('sys_dept.id', ondelete='SET NULL'), default=None, index=True, comment='父部门ID'
     )
     parent: Mapped[Union['Dept', None]] = relationship(init=False, back_populates='children', remote_side=[id])
     children: Mapped[list['Dept'] | None] = relationship(init=False, back_populates='parent')
+
     # 部门用户一对多
     users: Mapped[list['User']] = relationship(init=False, back_populates='dept')  # noqa: F821
diff --git a/backend/app/admin/model/sys_dict_data.py b/backend/app/admin/model/sys_dict_data.py
index 884bdc6b..4eac82b6 100644
--- a/backend/app/admin/model/sys_dict_data.py
+++ b/backend/app/admin/model/sys_dict_data.py
@@ -18,6 +18,9 @@ class DictData(Base):
     sort: Mapped[int] = mapped_column(default=0, comment='排序')
     status: Mapped[int] = mapped_column(default=1, comment='状态（0停用 1正常）')
     remark: Mapped[str | None] = mapped_column(LONGTEXT, default=None, comment='备注')
+
     # 字典类型一对多
-    type_id: Mapped[int] = mapped_column(ForeignKey('sys_dict_type.id'), default=0, comment='字典类型关联ID')
+    type_id: Mapped[int] = mapped_column(
+        ForeignKey('sys_dict_type.id', ondelete='CASCADE'), default=0, comment='字典类型关联ID'
+    )
     type: Mapped['DictType'] = relationship(init=False, back_populates='datas')  # noqa: F821
diff --git a/backend/app/admin/model/sys_dict_type.py b/backend/app/admin/model/sys_dict_type.py
index 3190162e..c5676b4a 100644
--- a/backend/app/admin/model/sys_dict_type.py
+++ b/backend/app/admin/model/sys_dict_type.py
@@ -17,5 +17,6 @@ class DictType(Base):
     code: Mapped[str] = mapped_column(String(32), unique=True, comment='字典类型编码')
     status: Mapped[int] = mapped_column(default=1, comment='状态（0停用 1正常）')
     remark: Mapped[str | None] = mapped_column(LONGTEXT, default=None, comment='备注')
+
     # 字典类型一对多
     datas: Mapped[list['DictData']] = relationship(init=False, back_populates='type')  # noqa: F821
diff --git a/backend/app/admin/model/sys_menu.py b/backend/app/admin/model/sys_menu.py
index f3233b2c..8b75d29e 100644
--- a/backend/app/admin/model/sys_menu.py
+++ b/backend/app/admin/model/sys_menu.py
@@ -6,7 +6,7 @@
 from sqlalchemy.dialects.mysql import LONGTEXT
 from sqlalchemy.orm import Mapped, mapped_column, relationship
 
-from backend.app.admin.model.sys_role_menu import sys_role_menu
+from backend.app.admin.model.m2m import sys_role_menu
 from backend.common.model import Base, id_key
 
 
@@ -29,13 +29,13 @@ class Menu(Base):
     show: Mapped[int] = mapped_column(default=1, comment='是否显示（0否 1是）')
     cache: Mapped[int] = mapped_column(default=1, comment='是否缓存（0否 1是）')
     remark: Mapped[str | None] = mapped_column(LONGTEXT, default=None, comment='备注')
+
     # 父级菜单一对多
     parent_id: Mapped[int | None] = mapped_column(
         ForeignKey('sys_menu.id', ondelete='SET NULL'), default=None, index=True, comment='父菜单ID'
     )
     parent: Mapped[Union['Menu', None]] = relationship(init=False, back_populates='children', remote_side=[id])
     children: Mapped[list['Menu'] | None] = relationship(init=False, back_populates='parent')
+
     # 菜单角色多对多
-    roles: Mapped[list['Role']] = relationship(  # noqa: F821
-        init=False, secondary=sys_role_menu, back_populates='menus'
-    )
+    roles: Mapped[list['Role']] = relationship(init=False, secondary=sys_role_menu, back_populates='menus')  # noqa: F821
diff --git a/backend/app/admin/model/sys_role.py b/backend/app/admin/model/sys_role.py
index acf46c01..415329f1 100644
--- a/backend/app/admin/model/sys_role.py
+++ b/backend/app/admin/model/sys_role.py
@@ -4,8 +4,7 @@
 from sqlalchemy.dialects.mysql import LONGTEXT
 from sqlalchemy.orm import Mapped, mapped_column, relationship
 
-from backend.app.admin.model.sys_role_menu import sys_role_menu
-from backend.app.admin.model.sys_user_role import sys_user_role
+from backend.app.admin.model.m2m import sys_role_menu, sys_user_role
 from backend.common.model import Base, id_key
 
 
@@ -19,11 +18,9 @@ class Role(Base):
     data_scope: Mapped[int | None] = mapped_column(default=2, comment='权限范围（1：全部数据权限 2：自定义数据权限）')
     status: Mapped[int] = mapped_column(default=1, comment='角色状态（0停用 1正常）')
     remark: Mapped[str | None] = mapped_column(LONGTEXT, default=None, comment='备注')
+
     # 角色用户多对多
-    users: Mapped[list['User']] = relationship(  # noqa: F821
-        init=False, secondary=sys_user_role, back_populates='roles'
-    )
+    users: Mapped[list['User']] = relationship(init=False, secondary=sys_user_role, back_populates='roles')  # noqa: F821
+
     # 角色菜单多对多
-    menus: Mapped[list['Menu']] = relationship(  # noqa: F821
-        init=False, secondary=sys_role_menu, back_populates='roles'
-    )
+    menus: Mapped[list['Menu']] = relationship(init=False, secondary=sys_role_menu, back_populates='roles')  # noqa: F821
diff --git a/backend/app/admin/model/sys_user.py b/backend/app/admin/model/sys_user.py
index dab80193..5a11d429 100644
--- a/backend/app/admin/model/sys_user.py
+++ b/backend/app/admin/model/sys_user.py
@@ -6,7 +6,7 @@
 from sqlalchemy import ForeignKey, String
 from sqlalchemy.orm import Mapped, mapped_column, relationship
 
-from backend.app.admin.model.sys_user_role import sys_user_role
+from backend.app.admin.model.m2m import sys_user_role
 from backend.common.model import Base, id_key
 from backend.database.db_mysql import uuid4_str
 from backend.utils.timezone import timezone
@@ -32,14 +32,15 @@ class User(Base):
     phone: Mapped[str | None] = mapped_column(String(11), default=None, comment='手机号')
     join_time: Mapped[datetime] = mapped_column(init=False, default_factory=timezone.now, comment='注册时间')
     last_login_time: Mapped[datetime | None] = mapped_column(init=False, onupdate=timezone.now, comment='上次登录')
+
     # 部门用户一对多
     dept_id: Mapped[int | None] = mapped_column(
         ForeignKey('sys_dept.id', ondelete='SET NULL'), default=None, comment='部门关联ID'
     )
     dept: Mapped[Union['Dept', None]] = relationship(init=False, back_populates='users')  # noqa: F821
-    # 用户角色多对多
-    roles: Mapped[list['Role']] = relationship(  # noqa: F821
-        init=False, secondary=sys_user_role, back_populates='users'
-    )
-    # 用户 OAuth2 一对多
+
+    # 用户社交信息一对多
     socials: Mapped[list['UserSocial']] = relationship(init=False, back_populates='user')  # noqa: F821
+
+    # 用户角色多对多
+    roles: Mapped[list['Role']] = relationship(init=False, secondary=sys_user_role, back_populates='users')  # noqa: F821
diff --git a/backend/app/admin/model/sys_user_role.py b/backend/app/admin/model/sys_user_role.py
deleted file mode 100644
index 1870360e..00000000
--- a/backend/app/admin/model/sys_user_role.py
+++ /dev/null
@@ -1,13 +0,0 @@
-#!/usr/bin/env python3
-# -*- coding: utf-8 -*-
-from sqlalchemy import INT, Column, ForeignKey, Integer, Table
-
-from backend.common.model import MappedBase
-
-sys_user_role = Table(
-    'sys_user_role',
-    MappedBase.metadata,
-    Column('id', INT, primary_key=True, unique=True, index=True, autoincrement=True, comment='主键ID'),
-    Column('user_id', Integer, ForeignKey('sys_user.id', ondelete='CASCADE'), primary_key=True, comment='用户ID'),
-    Column('role_id', Integer, ForeignKey('sys_role.id', ondelete='CASCADE'), primary_key=True, comment='角色ID'),
-)
diff --git a/backend/app/admin/model/sys_user_social.py b/backend/app/admin/model/sys_user_social.py
index 42c8833a..50439aa6 100644
--- a/backend/app/admin/model/sys_user_social.py
+++ b/backend/app/admin/model/sys_user_social.py
@@ -20,7 +20,8 @@ class UserSocial(Base):
     union_id: Mapped[str | None] = mapped_column(String(20), default=None, comment='第三方用户的 union id')
     scope: Mapped[str | None] = mapped_column(String(120), default=None, comment='第三方用户授予的权限')
     code: Mapped[str | None] = mapped_column(String(50), default=None, comment='用户的授权 code')
-    # 用户 OAuth2 一对多
+
+    # 用户社交信息一对多
     user_id: Mapped[int | None] = mapped_column(
         ForeignKey('sys_user.id', ondelete='SET NULL'), default=None, comment='用户关联ID'
     )