Disclosed is a suspension subframe (1) in which highly rigid side-end members (10) are attached to opposite side end sections of a flat plate-like main body member (2) so as to extend in the front-rear direction of a vehicle. The subframe (1) has extremely high rigidity against forces acting thereon from the front, rear, left, right and the like with the aid of the side-end members (10). The subframe (1) makes it possible to cut out materials with almost zero waste, and is made lightweight and inexpensive.