diff --git a/backend/app/models/level.py b/backend/app/models/level.py
index 239fa20..da39bf3 100644
--- a/backend/app/models/level.py
+++ b/backend/app/models/level.py
@@ -17,7 +17,7 @@ from sqlalchemy.orm import relationship
 from app.models.base import Base, BaseModel
 
 
-class UserLevel(BaseModel):
+class UserLevel(Base):
     """用户等级表"""
     __tablename__ = "user_levels"
 
@@ -30,16 +30,14 @@ class UserLevel(BaseModel):
     max_login_streak = Column(Integer, nullable=False, default=0, comment="历史最长连续登录天数")
     last_login_date = Column(Date, nullable=True, comment="最后登录日期")
     last_checkin_at = Column(DateTime, nullable=True, comment="最后签到时间")
+    created_at = Column(DateTime, nullable=False, default=datetime.now)
+    updated_at = Column(DateTime, nullable=False, default=datetime.now, onupdate=datetime.now)
     
     # 关联
     user = relationship("User", backref="user_level", uselist=False)
-    
-    # 不继承 is_deleted 等软删除字段
-    is_deleted = None
-    deleted_at = None
 
 
-class ExpHistory(BaseModel):
+class ExpHistory(Base):
     """经验值历史表"""
     __tablename__ = "exp_history"
 
@@ -51,16 +49,13 @@ class ExpHistory(BaseModel):
     description = Column(String(255), nullable=False, comment="描述")
     level_before = Column(Integer, nullable=True, comment="变化前等级")
     level_after = Column(Integer, nullable=True, comment="变化后等级")
+    created_at = Column(DateTime, nullable=False, default=datetime.now)
     
     # 关联
     user = relationship("User", backref="exp_histories")
-    
-    # 不继承软删除字段
-    is_deleted = None
-    deleted_at = None
 
 
-class BadgeDefinition(BaseModel):
+class BadgeDefinition(Base):
     """奖章定义表"""
     __tablename__ = "badge_definitions"
 
@@ -76,16 +71,14 @@ class BadgeDefinition(BaseModel):
     exp_reward = Column(Integer, nullable=False, default=0, comment="奖励经验值")
     sort_order = Column(Integer, nullable=False, default=0, comment="排序")
     is_active = Column(Boolean, nullable=False, default=True, comment="是否启用")
+    created_at = Column(DateTime, nullable=False, default=datetime.now)
+    updated_at = Column(DateTime, nullable=False, default=datetime.now, onupdate=datetime.now)
     
     # 关联
     user_badges = relationship("UserBadge", back_populates="badge")
-    
-    # 不继承软删除字段
-    is_deleted = None
-    deleted_at = None
 
 
-class UserBadge(BaseModel):
+class UserBadge(Base):
     """用户奖章表"""
     __tablename__ = "user_badges"
 
@@ -95,14 +88,11 @@ class UserBadge(BaseModel):
     unlocked_at = Column(DateTime, nullable=False, default=datetime.now, comment="解锁时间")
     is_notified = Column(Boolean, nullable=False, default=False, comment="是否已通知")
     notified_at = Column(DateTime, nullable=True, comment="通知时间")
+    created_at = Column(DateTime, nullable=False, default=datetime.now)
     
     # 关联
     user = relationship("User", backref="badges")
     badge = relationship("BadgeDefinition", back_populates="user_badges")
-    
-    # 不继承软删除字段
-    is_deleted = None
-    deleted_at = None
 
 
 class LevelConfig(Base):