Abstract: It is a kind of multistage wave rotor refrigerator which could be used in the field of gas expansion refrigeration. The refrigerator is mainly composed of a casing, a left end cover, a right end cover, a wave rotor, a central shaft, a high pressure inlet nozzle, a medium pressure outlet nozzle and a drive mechanism. Within the structure of the refrigerator, 2-8 times unsteady expansion of gas could get realized, which improves the refrigeration efficiency under large pressure ratio. Extending the structure of the refrigerator and changing the structure of end cover could help realize multistage expansion refrigeration of gas. The double opening structure of oscillation tubes could help the refrigerator work regularly with high moisture content of gas. This refrigerator is a gas expansion refrigeration device that uses moving unsteady pressure waves in oscillation tubes to realize the separation of the heat and cold of gas.