diff --git a/app/models.py b/app/models.py
index e76aa32..c21c43f 100644
--- a/app/models.py
+++ b/app/models.py
@@ -17,12 +17,14 @@ class User(Base):
     username = Column(String(64), unique=True, nullable=False, index=True)
     password_hash = Column(String(128), nullable=False)
     is_admin = Column(Boolean, nullable=False, default=False)
+    invited_by_code_id = Column(Integer, ForeignKey("invite_codes.id", ondelete="SET NULL"), nullable=True)
     showcase_mode = Column(String(16), nullable=False, default="profile")
     created_at = Column(DateTime, default=_utcnow)
 
     profiles = relationship("Profile", back_populates="user", cascade="all, delete-orphan")
     sessions = relationship("UserSession", back_populates="user", cascade="all, delete-orphan")
     invite_codes = relationship("InviteCode", back_populates="creator", cascade="all, delete-orphan")
+    invited_by_code = relationship("InviteCode", foreign_keys=[invited_by_code_id])
 
 
 class InviteCode(Base):
@@ -37,6 +39,7 @@ class InviteCode(Base):
     created_at = Column(DateTime, default=_utcnow)
 
     creator = relationship("User", back_populates="invite_codes")
+    registered_users = relationship("User", back_populates="invited_by_code", foreign_keys="User.invited_by_code_id")
 
 
 class UserSession(Base):
diff --git a/app/routers/web.py b/app/routers/web.py
index bb5a5fc..2f6b059 100644
--- a/app/routers/web.py
+++ b/app/routers/web.py
@@ -153,7 +153,7 @@ def register_submit(
             "register.html", {"request": request, "error": "用户名已存在"}, status_code=400
         )
     # Create user
-    new_user = User(username=username, password_hash=hash_password(password))
+    new_user = User(username=username, password_hash=hash_password(password), invited_by_code_id=code_obj.id)
     db.add(new_user)
     db.flush()
     # Update invite code usage
diff --git a/app/templates/admin_invites.html b/app/templates/admin_invites.html
index 0d6cd55..6a06661 100644
--- a/app/templates/admin_invites.html
+++ b/app/templates/admin_invites.html
@@ -61,6 +61,9 @@
             {% else %}
                 <span class="badge">永不过期</span>
             {% endif %}
+            {% if c.registered_users %}
+                <span class="badge" style="background:#e8f5e9">注册用户: {{ c.registered_users|map(attribute='username')|join(', ') }}</span>
+            {% endif %}
         </div>
         <form method="post" action="/admin/invites/{{ c.id }}/edit" class="admin-invite-form" id="edit-form-{{ c.id }}">
             <div class="aif-field">