Provided is an air conditioning refrigeration system. An outlet of a high-back-pressure rotary compressor is connected with an inlet of a condenser, an outlet of the condenser is connected with a liquid inlet of a heat regenerator, a liquid outlet of the heat regenerator is connected with an inlet of an expansion valve, an outlet of the expansion valve is connected with an inlet of an evaporator, an outlet of the evaporator is connected with a gas inlet of the heat regenerator, and a gas outlet of the heat regenerator is connected with an inlet of the high-back-pressure rotary compressor. Refrigerating fluid enters the high-back-pressure rotary compressor firstly, and is compressed into high-temperature high-pressure gas entering the condenser, the gas is condensed into intermediate-temperature high-pressure liquid, and heat is discharged into air. The refrigerating fluid flows through the heat regenerator and enters the expansion valve, and is throttled to be in a low-temperature low-pressure gas-liquid mixing state, then the refrigerating fluid enters the evaporator, heat exchange is carried out on the refrigerating fluid and the air in the environment, the temperature of the air is reduced, and therefore the refrigeration effect is achieved. According to the system, efficiency and stability are improved, oil return is good, the probability of blocking capillary tubes is reduced, and the injection amount of the refrigerating fluid is reduced.