The invention relates to cryogenic engineering. The inventive device for liquefying and separating gas and for releasing one or more gases from a mixture thereof, comprises, in series axially positioned, a prechamber (1) with gas flow whirling means (2) arranged therein, a subsonic or supersonic nozzle (3) with a working segment (4), which is abutted thereto and to which liquid phase extracting means (5) is connected, and a subsonic diffuser (7) or the combination of a supersonic (6) and the subsonic diffuser (7). The length of the working segment (4) is selected according to a condition of forming condensate drops with a size greater than 0.5 mkm and of drifting them, by centrifugal forces, from the axial area of the working segment to the walls of the drop extracting means. The device is provided with an additional nozzle (8) arranged in the prechamber. The invention makes it possible to increase the separation efficiency.