To provide a polystyrene resin foamed sheet suitable for a method of producing a foamed molded product by performing a thermoforming process of forming a plurality of product shapes in the longitudinal direction of a band-shaped polystyrene resin foamed sheet and then a cutting process for cutting the formed polystyrene resin foamed sheet with the product shapes into respective product shapes by a heating wire.

The band-shaped polystyrene resin foamed sheet 1, which is extruded in the longitudinal direction, is formed by performing an extrusion process of extruding and foaming a polystyrene resin composition from an annular discharge port of a circular die to form a cylindrical foamed product, and an opening process of cutting and opening the foamed product. In the polystyrene resin foamed sheet, when heated at 125°C for 90 seconds, a predetermined relationship is established between a heating shrinkage factor A (%) in the extrusion direction observed on the side corresponding to the outside surface of the foamed product and a heating shrinkage factor B (%) on the side corresponding to the inside surface of the foamed product.