A heat sink that can reduce a load imposed on a heat pipe and enhance a heat transfer efficiency from a heating body to a heat radiation fin is provided.The heat sink has a base plate 21 having a heat receiving portion to which a semiconductor device 11 is thermally connected, a heat pipe disposed on the base plate 21 while partially brought into contact with the heat receiving portion, and a heat radiation fin arranged to be stacked on the base plate 21 and the heat pipe 22. The base plate 21 is formed of a metal plate and has an opening portion 35 at the site corresponding to the heat receiving portion, and the heat receiving plate 36 which is formed of a metal plate having higher thermal conductivity than the base plate 21 is arranged to form substantially the same plane with the base plate 21.