: Economic and productive enterprising in current competitive market, in order to achieve competitive advantage or advantages whit the goal of achieving greater share of market, need to manage and control the related resources and components out of organization, in addition to addressing to internal organization and resources. Suppliers are one of these components. The actions which an organization take in order to evaluate and select efficient suppliers, lead to creation of competitive advantage and better performance of organization. One of the methods used to evaluate the efficiency of suppliers is Data Envelopment Analysis (DEA). The advantage and main characteristics of this method is its efficiency when there are more than one inputs and outputs so that the method is self calculates the weights related to input and outputs. The conditions are usually uncertain in real world efficiency of supplier should be evaluated under uncertainty conditions. In this research fuzzy sets theory and credibility measure is used to face uncertainty conditions. Also it was shown that credibility measure is proper measure to express the chance of fuzzy events. In order to evaluate the overall performance of DMU, it should be viewed from both optimistic and pessimistic point of view, so fuzzy DEA model from both viewpoints were suggested so that the concept of interval efficiency were defined then interval efficiencies were ranked and the results were compared with DEA fuzzy present models in different levels of reliability and were analyzed. Finally the suggested DEA fuzzy model was applied in submarine science and technology at Isfahan University of technology for selecting and evaluating the project suppliers. Superior suppliers of submarine components were recognized and suggested.