Abstract: A foldable luggage bag includes a collapsible luggage body, a rigid reinforcing member, and a wheel seat arrangement. The collapsible luggage body has a top surface, a bottom surface, a plurality of side surfaces extended between the top surface and the bottom surface, and a receiving cavity. The rigid reinforcing member has a bottom reinforcing portion mounted at the bottom surface, a plurality of side reinforcing portions formed on lower portions of the side surfaces of the collapsible luggage body, and a plurality of curved reinforcing portions integrally extended between the bottom reinforcing portion and the side reinforcing portions of the rigid reinforcing member respectively. The wheel seat arrangement includes a plurality of wheel seats and a plurality of rolling wheels received in the wheel seat, so that the collapsible luggage body is rotatably supported by the rolling wheels and is substantially protected by the rigid reinforcing member.