The invention relates to a low-temperature refrigeration process in an ethylene storing process. The low-temperature refrigeration process is characterized in that a separate refrigeration system is not required; and a refrigerant such as ammonia, dichlorodifluoromethane and the like is not used, instead, ethylene is used as the refrigerant to realize cooling. The low-temperature refrigeration process comprises the steps as follows: after flash evaporation and cooling of liquid ethylene in an ethylene buffer tank V-01 is carried out, gaseous ethylene in the system is condensed through an ethylene condenser E-02; at the same time, an expansion machine ET-01 is used for providing refrigerating capacity supplement for the system; ethylene which is gasified through heat absorption of a storing system is heated by high-temperature gas at an outlet of a compressor in an ethylene condenser E-04, and then enters the compressor C-01 so as to raise the gas inlet temperature of the compressor and the usage of a low-temperature compressor is avoided; and heat exchangers E-03 and E-04 are used for recovering the refrigerating capacity repeatedly, so that the operating cost is reduced. When the system is initially started, feeding ethylene with lower temperature is used for condensing ethylene containing inert gases, a condensing system is pre-cooled, and the ethylene emission is reduced. Energy consumption can be reduced, the cost can be saved, the construction investment can be reduced, and at the same time, the stability of the device is improved.