For today there is no single universal methodology for evaluating and selecting a supplier. Each commercial organization develops an assessment methodology individually, based on a variety of criteria that are considered important, or focusing on the cost of purchase. The downside of choosing a vendor based on cost criteria only is ignoring other significant criteria, while systems with multiple criteria often allow valuation bias and options for result manipulation. In this article modern methods of supplier evaluation are analyzed, giving more attention to the most common ones. Taking into account their merits and shortcomings, the author's combined method has been developed, which consists in simultaneously assessing the supplier with multicriteria and single-criteria (total cost method) methods and decision-making using the Edgeworth-Pareto method. Pareto-suboptimal solutions are cut off by an algorithm based on Pareto optimal set formula. The remaining options are assessed by the purchasing manager in terms of strategic importance by applying the "strategic matrix of supplier choice" proposed by the authors. It is a modification of Kralich matrix, adapted to the task of supplier selection, for which the author's scale of assessment is proposed. The proposed supplier evaluation method allows to compare the financial benefits of selecting a particular supplier and a combination of other significant factors, and make an informed managerial decision.