To provide a seat receiver and a chair for evading failures such as the interference of members and component increase in a uniform and simple structure which can be produced at a low cost.

The seat receiver is in a box shape provided with a bottom wall 15, side walls 19a and 19b raised from two opposing side edges of the bottom wall 15 and inclined walls 16 and 17 which are front and back direction walls raised from the front edge and rear edge of the bottom wall 15, whose opposing two side edges are respectively connected to the corresponding side walls 19a and 19b. It is constituted by bending one plate material 10.