It is a complex situation when a decision is to be made under uncertainty. The uncertain information has been treated mathematically in the literature from different angles. This paper presents a novel method towards this problem based on fuzzy sets. The approach is constituted using distance between triangular fuzzy numbers. The proposed approach allows decision makers (DMs) to evaluate and improve supplier selection decisions in an uncertain situation. Finally, a numerical example on the supplier selection problem is proposed to illustrate an application of the methodology.