This paper describes a new ejector refrigeration system with mechanical subcooling which uses an auxiliary liquid-gas ejector to enhance subcooling for the refrigerant from condenser. The new system can have larger subcooling degree when circulating pump consumes a little more power compared with conventional ejector refrigeration system. Based on the built mathematical model, the performance of the new ejector refrigeration system was discussed and compared with that of a conventional ejector refrigeration system for refrigerant R142b. Theoretical analyzing results show that the new system can efficiently improve the coefficient of performance (COP) of ejector refrigeration. (c) 2006 Elsevier Ltd. All rights reserved.