A refrigeration cycle device comprising: a main refrigerant circuit formed by sequentially connecting, to one another through a pipe, a compression mechanism composed of compression rotation elements (21a, 21b), a usage-side heat exchanger for heating usage-side heat medium by refrigerant discharged from the compression rotation element, an intermediate heat exchanger, a first expansion device and a heat source-side heat exchanger; a bypass refrigerant circuit which exchanges heat with refrigerant flowing through the main refrigerant circuit by the intermediate heat exchanger after refrigerant branching off from the pipe between the usage-side heat exchanger and the first expansion device is decompressed by a second expansion device of the refrigeration cycle device, the bypass refrigerant circuit joining up with refrigerant which is being compressed of the compression rotation element; a blowing device for supplying air to the heat source-side heat exchanger; and a control device, the refrigeration cycle device further includes a heating operation mode for heating the usage-side heat medium in the usage-side heat exchanger by refrigerant discharged from the compression rotation element, a defrosting operation mode for removing frost of the heat source-side heat exchanger by refrigerant discharged from the compression rotation element, the control device is configured to execute the heating operation mode and the defrosting operation mode, characterized in that in the defrosting operation mode, a valve opening degree of the first expansion device is made large, high temperature and high pressure gas refrigerant discharged from the compression mechanism is made to pass through the first expansion device without decompressing the gas refrigerant, and refrigerant discharge from the compression rotation element flows through the usage-side heat exchanger, the first expansion device and the heat source-side heat exchanger in this order, wherein the control device is configured to execute the defrosting operation mode to melt frost adhering to the heat source-side heat exchanger and thereafter, the execution of the defrosting operation mode is completed, in the heating operation mode which is executed after the defrosting operation mode is completed, at least for a predetermined period during execution of the heating operation mode, the control device sets opening degrees of the first expansion device and the second expansion device to such values that a flow rate of refrigerant flowing through the first expansion device becomes greater than a flow rate of refrigerant flowing through the second expansion device, and the blowing device is operated. a main refrigerant circuit formed by sequentially connecting, to one another through a pipe, a compression mechanism composed of compression rotation elements (21a, 21b), a usage-side heat exchanger for heating usage-side heat medium by refrigerant discharged from the compression rotation element, an intermediate heat exchanger, a first expansion device and a heat source-side heat exchanger; a bypass refrigerant circuit which exchanges heat with refrigerant flowing through the main refrigerant circuit by the intermediate heat exchanger after refrigerant branching off from the pipe between the usage-side heat exchanger and the first expansion device is decompressed by a second expansion device of the refrigeration cycle device, the bypass refrigerant circuit joining up with refrigerant which is being compressed of the compression rotation element; a blowing device for supplying air to the heat source-side heat exchanger; and a control device, the refrigeration cycle device further includes a heating operation mode for heating the usage-side heat medium in the usage-side heat exchanger by refrigerant discharged from the compression rotation element, a defrosting operation mode for removing frost of the heat source-side heat exchanger by refrigerant discharged from the compression rotation element, the control device is configured to execute the heating operation mode and the defrosting operation mode, characterized in that in the defrosting operation mode, a valve opening degree of the first expansion device is made large, high temperature and high pressure gas refrigerant discharged from the compression mechanism is made to pass through the first expansion device without decompressing the gas refrigerant, and refrigerant discharge from the compression rotation element flows through the usage-side heat exchanger, the first expansion device and the heat source-side heat exchanger in this order, wherein the control device is configured to execute the defrosting operation mode to melt frost adhering to the heat source-side heat exchanger and thereafter, the execution of the defrosting operation mode is completed, in the heating operation mode which is executed after the defrosting operation mode is completed, at least for a predetermined period during execution of the heating operation mode, the control device sets opening degrees of the first expansion device and the second expansion device to such values that a flow rate of refrigerant flowing through the first expansion device becomes greater than a flow rate of refrigerant flowing through the second expansion device, and the blowing device is operated.