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The recovery of the available waste heat from the operating engines of a modern cruise ship plays an important role in the reduction of the environmental impact of these huge means of transport. The cooling load required by the ship passengers can be handled with innovative air-conditioning systems that employ a vapor single-phase ejector and are fed by waste heat. On the contrary, these systems are usually more expensive than vapor compression cycles, representing the conventional technology. In this paper, a thermo-economic-environmental analysis of a combined cooling system for a cruise ship operating in the Baltic Sea is proposed. Two different cooling plants are compared, namely a typical vapor compression cycle and a multiejector hybrid ejector cycle integrated with a cold storage tank aiming to buffer the load variations. The approach is numerical, and the simulations are carried-out with dedicated sub-models for each component. Volumetric machines (pumps, compressor) are modeled through phenomenological equations, calibrated and validated on real data, whereas the heat exchangers are simulated by using specific heat transfer prediction methods and typical geometries. The objective is to size the whole system and optimize the tank size and the control strategy, to minimize the investment cost and maximize the seasonal performance. Also, an economic comparison, concerning the total costs (investments costs plus operating costs) between the solution chosen and the reference one has been carried out considering the fuel cost as a parametric input. Finally, an environmental analysis is performed to assess the reduction in pollutant emissions with the proposed system.