A refrigeration cycle apparatus (100, 200, 300) comprising: a refrigerant circuit configured by connecting a compressor, a refrigerant flow switching device, a first heat exchanger, a first pressure reducing device, a refrigerant container, a second pressure reducing device, and a second heat exchanger by a pipe; a bypass guiding at least part of a refrigerant accumulated in the refrigerant container toward a suction side of the compressor through a third pressure reducing device and a refrigerant heat exchanger, a controller, a first on/off valve provided between a discharge side of the compressor and the second heat exchanger and being controlled by the controller; and a second on/off valve provided between the refrigerant flow switching device and the second heat exchanger and being controlled by the controller, wherein the refrigerant heat exchanger is provided within the refrigerant container, and configured to exchange heat between a flow of the refrigerant that circulates in the pypass and a flow of the refrigerant that is accumulated in the refrigerant container, and when the first heat exchanger functions as an evaporator and the second heat exchanger functions as a condenser, the first on/off valve is opened and the second on/off valve is closed, and the refrigerant discharged from the compressor is caused to flow into both the first heat exchanger and the second heat exchanger to perform a defrosting operation of the first heat exchanger, the refrigerant from the first heat exchanger and the refrigerant from the second heat exchanger merge in the refrigerant container, and then the merged refrigerant is caused to flow to a suction side of the compressor, wherein the refrigeration cycle apparatus (100, 200, 300) further comprising: a gas return pipe communicatively connected to an inside of the refrigerant container; and a third on/off valve provided in the gas return pipe, wherein one end of the gas return pipe is connected to the suction side of the compressor. a refrigerant circuit configured by connecting a compressor, a refrigerant flow switching device, a first heat exchanger, a first pressure reducing device, a refrigerant container, a second pressure reducing device, and a second heat exchanger by a pipe; a bypass guiding at least part of a refrigerant accumulated in the refrigerant container toward a suction side of the compressor through a third pressure reducing device and a refrigerant heat exchanger, a controller, a first on/off valve provided between a discharge side of the compressor and the second heat exchanger and being controlled by the controller; and a second on/off valve provided between the refrigerant flow switching device and the second heat exchanger and being controlled by the controller, wherein the refrigerant heat exchanger is provided within the refrigerant container, and configured to exchange heat between a flow of the refrigerant that circulates in the pypass and a flow of the refrigerant that is accumulated in the refrigerant container, and provided within the refrigerant container, and configured to exchange heat between a flow of the refrigerant that circulates in the pypass and a flow of the refrigerant that is accumulated in the refrigerant container, and when the first heat exchanger functions as an evaporator and the second heat exchanger functions as a condenser, the first on/off valve is opened and the second on/off valve is closed, and the refrigerant discharged from the compressor is caused to flow into both the first heat exchanger and the second heat exchanger to perform a defrosting operation of the first heat exchanger, the refrigerant from the first heat exchanger and the refrigerant from the second heat exchanger merge in the refrigerant container, and then the merged refrigerant is caused to flow to a suction side of the compressor, wherein the refrigeration cycle apparatus (100, 200, 300) further comprising: a gas return pipe communicatively connected to an inside of the refrigerant container; and a third on/off valve provided in the gas return pipe, wherein one end of the gas return pipe is connected to the suction side of the compressor. a gas return pipe communicatively connected to an inside of the refrigerant container; and a third on/off valve provided in the gas return pipe, wherein one end of the gas return pipe is connected to the suction side of the compressor.