A semiconductor device includes a semiconductor chip, a heat sink, a resin package, heat transfer material and multiple spacers. The heat sink absorbs heat of the semiconductor chip. The resin package accommodates the semiconductor chip, and the resin package has a surface at which the heat sink is disposed. The heat transfer material has fluidity, and the heat transfer material is filled between the heat sink and the cooling plate. The spacers are dispersedly arranged in the heat transfer material, and the spacers are in contact with the heat sink and the cooling plate.