A heat storage apparatus capable of efficiently storing heat emitted from a compressor and air conditioner having the heat storage apparatus. An air conditioner includes a heat storage apparatus for storing heat emitted from a compressor arranged in an outdoor unit, wherein the heat storage apparatus includes a heat storage tank installed in the compressor for storing heat emitted from the compressor and a heat transfer member configured to deliver heat emitted from the compressor to the heat storage tank, wherein the heat storage tank includes a first heat transfer face configured to have a form corresponding to a part of an outer circumferential face of the compressor to come into contact with the outer circumferential face of the compressor and a pair of second heat transfer faces configured to extend from both ends of the first heat transfer face to be in parallel to each other and form space with the outer circumferential face of the compressor, and wherein the heat transfer member is arranged in the space.