Abstract: A method of forming a plastic molded article includes expansion molding of a plastic raw material mixed with a blowing material. In a first step, a first-stage expansion molding is used to form a core. This is followed by a second step in which a second-stage expansion molding is employed to produce an outer layer around the previously-formed core, in such a manner that the outer layer is fusion bonded and integrated with a boundary region of the core, thereby forming a second-stage molded product. At least the outer layer contains randomly distributed resin fibers.