A method is disclosed for forming a foamed aluminum article. A foaming vessel is used including a peripheral wall and a plurality of vertical rod members to form mounting holes at given positions in the vicinity of the inside surface of the peripheral wall. The melt of aluminum or its alloy is stirred with a viscosity increaser and a foaming material. The solidified aluminum block is then sliced to a given thickness to obtain a product of foamed aluminum having mounting holes in given positions in the vicinity of the outer edge thereof. A hard portion around the holes is used as the surface site for mounting the product. The products are used for sound and heat insulation.