A refrigeration cycle device includes a compressor configured to compress and discharge a refrigerant containing oil, a refrigerant radiator configured to heat the ventilation air using the refrigerant discharged from the compressor as a heat source during a room interior heating, a refrigerant decompression unit configured to decompress the refrigerant having passed through the refrigerant radiator, an evaporator configured to evaporate the refrigerant and to function as a heat absorber during the room interior heating; and a controller configured to control the refrigerant decompression unit and to perform a fluctuation operation at least during the room interior heating. In the fluctuation operation, a throttle opening degree of the refrigerant decompression unit is changed such that a refrigerant state on a refrigerant outlet side of the evaporator is alternately changed to a superheated state having a superheat degree and a wet state containing the wet vapor.