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A simple ejector refrigeration cycle (ERC) has much lower operating cost in comparison with that for vapor compression refrigeration cycle (VCRC), however it has low coefficient of performance (COP). A combined (hybrid) ejector-compressor refrigeration cycle (CECRC) improves the COP of ERC considerably and still has a low operating cost. A novel two-step method is proposed here to improve the optimum design method of CECRC. The method applies system modeling and multi-objective optimizing of CECRC system (the first step which is not observed in literature) as well as computational fluid dynamics for flow analysis inside ejector (the second step). Results of applying the novel proposed method show that CECRC has C O P t h r = 0.76 in comparison with 0.31 for ejector refrigeration cycle (147% increase) and has C O P m e c h = 11.45 in comparison with 7.73 for compressor refrigeration cycle (48% increase). This COP is even considerably bigger than that reported by other researchers who have studied and designed CECRC and have reported their results for this system in literature. Furthermore for the optimized CECRC, the exergy efficiency ηexergy is about 40% in comparison with 30.6% for ejector refrigeration cycle (increase for 31%). Finally the operational cost (electrical power consumption cost) for providing one refrigeration ton cooling capacity (79.1 $ y e a r − 1 ) is lower than that for compression refrigeration cycle (117.4 $ y e a r − 1 ) which shows 33% reduction.