An object of the present disclosure is to provide a heat sink that can equalize heat input in a heat receiving portion and increase a volume of the heat receiving portion, prevent an increase in heat resistance in the heat receiving portion even when a heat generation amount from a heat-generating element increases, and exhibit excellent cooling performance with respect to a cooling target.There is provided a heat sink including: a heat transport member having a heat receiving portion thermally connected to a heat-generating element; a tube body connected to a heat insulating portion or a heat radiating portion of the heat transport member; and a heat radiation fin group which is thermally connected to the tube body and in which a plurality of heat radiation fins are arranged, in which the heat transport member has an integral internal space that communicates from the heat receiving portion to a connection portion with the tube body and is sealed with a working fluid, and the internal space of the heat transport member communicates with an internal space of the tube body.