To provide a seatback for a vehicle seat capable of effectively absorbing a load received from a crew during the application of an impulse load.

A seatback 13 includes a frame 17 formed with its lower end connected to the rear end of a seat cushion 12 and its upper end extending corresponding to the rear side of the head 19b of a seated crew and a pad 16 formed of soft plastic foam so as to cover the front face of the frame 17. A hard plastic foam 21 is provided between the front face of the frame 17 corresponding to the rear side of the head 10b of the crew and the pad 16. The plastic foam is polyurethane foam.