An optimal planning method is presented for a cascade-type multistage refrigeration system. Heat exchange areas of evaporator, condenser, and beverage cooler are determined optimally so as to minimize the annual total cost and input energy consumption subject to constraints concerning annual equipment operation. This problem is considered as a multiobjective optimization one, and a discrete set of Pareto optimal solutions is derived numerically by a weighting method. Through a numerical study, it is investigated how the heat exchange areas influence the long-term economics and energy conservation. Cascade-type multistage refrigeration systems are compared with single-stage systems.