<p>An air conditioning device provided with a refrigerant circuit for performing a supercritical refrigeration cycle by two-stage compression, wherein the air conditioning device is provided with an ice heat storage tank (2) which provides, without an increase in the amount of electric power consumption by a compressor, the air conditioning device with refrigeration ability close to the refrigeration ability of an air conditioning device using a current HFC-based refrigerant. The ice heat storage tank (2) stores therein water or ice as a heat storage medium and is provided with a heat storage heat exchanger (14) connected to a refrigerant circuit (10) and exchanging heat between the heat storage medium and the refrigerant in the refrigerant circuit (10). The ice heat storage tank (2) functioning as a heat dissipater when the heat storage heat exchanger (14) utilizes cold energy of the heat storage medium is provided between a low-stage compressor (11a) and a high-stage compressor (11b) of the air conditioning device (1).</p>
