Purchasing is one of the most important strategic activities in supply chain. One of the most critical functions in purchasing is to select supplier. Suppliers have a large effect on cost of products and services in organizations and corporations. One of the models used in selecting suppliers is data envelopment analysis (DEA). Traditional DEA models such as CCR and BCC can only measure radial efficiency (weak efficiency). To measure strong efficiency in DEA, Tone (2001) proposed slacks-based measure (SBM). This model deals directly with the input excesses and output shortfalls. The objective of this paper is to propose an imprecise SBM for selecting the best suppliers. This model can consider simultaneously imprecise data and strong efficiency for supplier selection problems.