The invention relates to a light low gravity-center baseplate for a vehicle. The baseplate contains two frames, a bottom plate and two longitudinal beams, which are made of aluminum alloy through extrusion, wherein each frame contains a frame top plate and a frame bottom plate which are arranged from top to bottom in parallel, a folding fan-shaped frame rib plate is arranged between the frame topplate and the frame bottom plate; the bottom plate contains a top plate A and a bottom plate A which are arranged from top to bottom in parallel, a rib plate A is arranged between the top plate A andthe bottom plate A; the upper surfaces of the two frames, the two longitudinal beams and the bottom plate are parallel mutually; the two frames, the two longitudinal beams and the bottom plate constitute a rectangular flat plate; and the longitudinal beams are higher than the frames. The invention aims to provide a vehicle light low gravity-center baseplate which has the advantages of high strength and rigidity, light dead weight, large utilizable space for the goods carriage, long service life, fewer parts used in manufacture and assembly, simple structure and short manufacturing period, is easy to assemble and can reduce the energy consumption in the movement of the vehicle and save energy.