A method for producing a vehicle seat member in which a frame member having protrusions is integrally molded to a foamed resin molded body is provided. The method comprises an in-mold foam molding step of placing the frame member in a mold, packing prefoamed resin particles, and molding the foamed resin molded body by in-mold foam molding; and a demolding step of removing the mold to obtain the vehicle seat member, wherein in the in-mold foam molding step, the foamed resin molded body is molded so that (B−A)/B is 13/1000 or less, wherein A is an outer dimension of the foamed resin molded body in the vehicle seat member obtained by the demolding step and B is an inner dimension of the mold corresponding to the outer dimension of the foamed resin molded body.