A regenerative air-conditioning apparatus comprising: an outdoor unit comprising a compressor and an outdoor heat exchanger; an indoor unit disposed on a side of the outdoor unit and comprising an indoor heat exchanger; a refrigerant tube connecting the outdoor unit to the indoor unit to guide circulation of a refrigerant and comprising a first connection tube connecting one side of the outdoor unit to one side of the indoor unit and a second connection tube connecting the other side of the outdoor unit to the other side of the indoor unit; a heat accumulation bath disposed on at least one side of the outdoor unit and the indoor unit to store cool air or heat; a first tube extending from the refrigerant tube to one side of the heat accumulation bath; a second tube extending from the other side of the heat accumulation bath to the refrigerant tube; and a third tube branched from the second tube, the third tube being connected to the refrigerant tube, wherein the apparatus further comprises: a first connection part disposed in the first connection tube connected to the third tube; a second connection part disposed in the first connection tube connected to the first tube, wherein the first tube extends from the second connection part to the heat accumulation bath; a first valve disposed between the first connection part and the second connection part; an expansion member disposed in the first tube to decompress the refrigerant flowing into the first tube; characterized in that the regenerative air-conditioning apparatus further comprises a bypass tube disposed on a side of the first tube to allow the refrigerant to bypass the expansion member, and a check valve disposed in the bypass tube to guide the refrigerant flowing into the bypass tube in one direction. an outdoor unit comprising a compressor and an outdoor heat exchanger; an indoor unit disposed on a side of the outdoor unit and comprising an indoor heat exchanger; a refrigerant tube connecting the outdoor unit to the indoor unit to guide circulation of a refrigerant and comprising a first connection tube connecting one side of the outdoor unit to one side of the indoor unit and a second connection tube connecting the other side of the outdoor unit to the other side of the indoor unit; a heat accumulation bath disposed on at least one side of the outdoor unit and the indoor unit to store cool air or heat; a first tube extending from the refrigerant tube to one side of the heat accumulation bath; a second tube extending from the other side of the heat accumulation bath to the refrigerant tube; and a third tube branched from the second tube, the third tube being connected to the refrigerant tube, wherein the apparatus further comprises: a first connection part disposed in the first connection tube connected to the third tube; a second connection part disposed in the first connection tube connected to the first tube, wherein the first tube extends from the second connection part to the heat accumulation bath; a first valve disposed between the first connection part and the second connection part; an expansion member disposed in the first tube to decompress the refrigerant flowing into the first tube; characterized in that the regenerative air-conditioning apparatus further comprises a bypass tube disposed on a side of the first tube to allow the refrigerant to bypass the expansion member, and a check valve disposed in the bypass tube to guide the refrigerant flowing into the bypass tube in one direction. a first connection part disposed in the first connection tube connected to the third tube; a second connection part disposed in the first connection tube connected to the first tube, wherein the first tube extends from the second connection part to the heat accumulation bath; a first valve disposed between the first connection part and the second connection part; an expansion member disposed in the first tube to decompress the refrigerant flowing into the first tube; characterized in that the regenerative air-conditioning apparatus further comprises a bypass tube disposed on a side of the first tube to allow the refrigerant to bypass the expansion member, and a check valve disposed in the bypass tube to guide the refrigerant flowing into the bypass tube in one direction.