diff --git a/alembic/versions/025_add_user_wechat_fields.py b/alembic/versions/025_add_user_wechat_fields.py
new file mode 100644
index 000000000..2e0ef4ee0
--- /dev/null
+++ b/alembic/versions/025_add_user_wechat_fields.py
@@ -0,0 +1,72 @@
+"""Task: Add wechat_openid / wechat_unionid to users
+
+Revision ID: 025
+Revises: 024
+Create Date: 2026-07-05
+
+补录微信小程序登录所需的 wechat 字段。
+生产数据库已手动添加过这些字段和索引，因此 upgrade 做幂等检查，
+避免在已有字段的库上执行报错。
+"""
+
+import sqlalchemy as sa
+
+from alembic import op
+
+revision = "025"
+down_revision = "024"
+branch_labels = None
+depends_on = None
+
+
+def _column_exists(table: str, column: str) -> bool:
+    """检查 PostgreSQL 表中某列是否已存在。"""
+    conn = op.get_bind()
+    result = conn.execute(
+        sa.text(
+            "SELECT 1 FROM information_schema.columns "
+            "WHERE table_name = :table AND column_name = :column"
+        ),
+        {"table": table, "column": column},
+    )
+    return result.scalar() is not None
+
+
+def _index_exists(index: str) -> bool:
+    """检查 PostgreSQL 中某索引是否已存在。"""
+    conn = op.get_bind()
+    result = conn.execute(
+        sa.text("SELECT 1 FROM pg_indexes WHERE indexname = :index"),
+        {"index": index},
+    )
+    return result.scalar() is not None
+
+
+def upgrade() -> None:
+    # wechat_openid
+    if not _column_exists("users", "wechat_openid"):
+        op.add_column(
+            "users",
+            sa.Column("wechat_openid", sa.String(length=128), nullable=True),
+        )
+
+    # wechat_unionid
+    if not _column_exists("users", "wechat_unionid"):
+        op.add_column(
+            "users",
+            sa.Column("wechat_unionid", sa.String(length=128), nullable=True),
+        )
+
+    # 唯一索引
+    if not _index_exists("ix_users_wechat_openid"):
+        op.create_index("ix_users_wechat_openid", "users", ["wechat_openid"], unique=True)
+
+    if not _index_exists("ix_users_wechat_unionid"):
+        op.create_index("ix_users_wechat_unionid", "users", ["wechat_unionid"], unique=True)
+
+
+def downgrade() -> None:
+    op.drop_index("ix_users_wechat_unionid", table_name="users")
+    op.drop_index("ix_users_wechat_openid", table_name="users")
+    op.drop_column("users", "wechat_unionid")
+    op.drop_column("users", "wechat_openid")
diff --git a/packages/adapters/sqlalchemy_impl/models.py b/packages/adapters/sqlalchemy_impl/models.py
index 94aaff0f4..982875e00 100755
--- a/packages/adapters/sqlalchemy_impl/models.py
+++ b/packages/adapters/sqlalchemy_impl/models.py
@@ -30,6 +30,9 @@ class UserModel(Base):
     used_storage_gb = Column(Integer, nullable=False, default=0)
     # 管理员标识
     is_admin = Column(Boolean, nullable=False, default=False)
+    # 微信登录（小程序端）
+    wechat_openid = Column(String(128), nullable=True, unique=True, index=True)
+    wechat_unionid = Column(String(128), nullable=True, unique=True, index=True)
     created_at = Column(DateTime, nullable=False, default=lambda: datetime.now(timezone.utc))