The present invention is an apparatus for dissipating heat through a heat sink, the apparatus comprising: a heat transfer member having one end with a contact surface contacting a heating element arranged on a substrate and the other end with a contact surface contacting the heat sink, the heat transfer member transferring the heat generated from the heating element to the heat sink; an elastic member for providing elastic force for pushing the heat transfer member toward the heating element; a guide member arranged in the heat sink to form a contact surface contacting the heat transfer member, the guide member mechanically guiding the heat transfer member such that the heat transfer member may slide and move toward the heating element; and a spacing member inserted between the substrate and the heat sink so as to maintain a preset spacing when the substrate and the heat sink are fixed and attached with each other.