diff --git a/Merge/back_wzy/models/comment.py b/Merge/back_wzy/models/comment.py
new file mode 100644
index 0000000..ce25287
--- /dev/null
+++ b/Merge/back_wzy/models/comment.py
@@ -0,0 +1,24 @@
+# models/comment.py
+from extensions import db
+from datetime import datetime
+
+class Comment(db.Model):
+    __tablename__ = 'comments'
+
+    id = db.Column(db.Integer, primary_key=True)
+    post_id = db.Column(db.Integer, db.ForeignKey('posts.id', ondelete='CASCADE'), nullable=False)
+    user_id = db.Column(db.Integer, db.ForeignKey('users.id', ondelete='CASCADE'), nullable=False)
+    parent_id = db.Column(db.Integer, db.ForeignKey('comments.id', ondelete='CASCADE'))
+    content = db.Column(db.Text, nullable=False)
+    status = db.Column(db.Enum('active', 'deleted'), default='active', nullable=False)
+    created_at = db.Column(db.DateTime, default=datetime.utcnow, nullable=False)
+    updated_at = db.Column(db.DateTime, default=datetime.utcnow,
+                           onupdate=datetime.utcnow, nullable=False)
+
+    # self-referential replies
+    replies = db.relationship(
+        'Comment',
+        backref=db.backref('parent', remote_side=[id]),
+        lazy='dynamic',
+        cascade='all, delete-orphan'
+    )