A body part of a decompression device is provided with a swirling space that allows a refrigerant from a refrigerant inlet to swirl, a throttle space that depressurizes the refrigerant that has flowed out of the swirling space, and a downstream-side space that is disposed on the downstream side of the throttle space in a refrigerant flow and is formed so that the pressure of a refrigerant present in the downstream-side space becomes uniform.