Researchers have been focused on refrigerant R744 because it is a natural refrigerant and its Global Warming Potential value is 1. However, coefficient of performance (COP) of refrigeration systems that use R744 as refrigerant has lower values than refrigeration systems that use CFC and HCFC refrigerants as refrigerant. Previous studies showed that COP of the refrigeration system with R744 can be increased by using twophase ejector. In this study, additional evaporators are used instead of the separator. Thus, the refrigeration system can be constructed more accurately. Theoretical analysis of the bievaporator refrigeration system with two-phase ejector is carried out by using energy and momentum equations. COP and entrainment ratio are obtained for various operating conditions. Results show that COP improvement can be achieved about 21% for proper design in Mediterranean climate zone.