回複：I-864 need U.S.citizenship?

Yes, you can and should use it. It is for your H4 spouse and child signed by you. If your spouse also H1 holder and works now, and you have no child, the I-864 is not necesarry, instead, your spuse should also obtain a statement from his/her empoloyer's Human Resource to comfirm that she/he has salary incoming.