The present invention solves the problem of realizing a lighter cushion body that has ample cushioning properties when a person sits or lies thereon by: providing a plurality of rod-shaped or flat plate-shaped support bodies (2) comprising a synthetic resin foam that has a bending deflection amount of 20 mm or more as measured according to the method described in JIS K7221-2:2006 and a pressing force of 2-100 N at 20 mm of deflection, and legs (3) on which the support bodies (2) are placed or fixed; using the support bodies and the legs to form a space (5) that makes it possible to bend and deform the support bodies; and arranging the plurality of rod-shaped or flat plate-shaped support bodies (2) in a row so as to be deformable.