The single-stage compression heat regenerative cycle of zeotropic refrigerant mixtures was studied. The Linde-Hampson refrigeration cycle characteristics and the main problems were analyzed. The refrigerant mixture R23 and R600a was discussed and selected suitable for -70℃ low temperature refrigerator according to the zeotropic mixture refrigerant properties. The refrigeration system characteristics of different ratio were discussed using refrigerant property analysis software NIST Refprop 8.0. It was compared with the performance of the system through experimental methods under different ratio of refrigerant mixture from different aspects. Finally the reasonable refrigerant mixture R23 / R600a component ratio 3:7 was obtained. The proportion of refrigeration compressor discharge temperature

pressure ratio

and low temperature refrigerator temperature change characteristics was analyzed. And the evaporator and the heat regenerator temperature change characteristics were discussed.