A compressed air energy storage power generation device includes a first heat exchanger, a heat storage tank, a second heat exchanger, a heating unit, a first power distributor, and a controller. The first heat exchanger performs heat exchange between the compressed air from a compressor and the heating medium. The heat storage tank stores the heating medium heatexchanged by the first heat exchanger. The second heat exchanger performs heat exchange between the compressed air from an accumulator tank and the heating medium from the heat storage tank. The first power distributor distributes the generated power of the power generator to a power system and the heating unit. When the internal pressure of the accumulator tank reaches a predetermined pressure and the generated power is larger than the power demand, the controller supplies a part or all of the generated power to the heating unit by the first power distributor.