At present, complex evaluation of medical devices is very topical. The methods of pharmacoeconomics and cost analyses appear to need some modifications caused by a different character of medical devices [1]. One of the approaches to this task is utilization of multi-criteria decision making [2]. In this study, a methodology for medical devices evaluation is suggested based on the multi-criteria decision making utilized to evaluate the effective part of the cost-effectiveness ratio. This analysis evaluates not only costs spent in the particulat technology (both procurement and operation costs), but also technical, user's and clinical parameters of the medical devices. Several methods of multi-criteria decision making were compared in this study, among others the ideal point method, the weighted sum approach (WSA) and the TOPSIS method. In the pilot implementation, these methods were applied to evaluate lung ventilator. The goal was to compare utilization of various methods, and to choose the optimum variant. The results were twofold. The TOPSIS method proved to be the best for evaluations for device procurement by medical units (clinics, hospitals). All comparisons were completed with a sensitivity analysis.