Evaluating and selecting alternatives investment projects needs considering all relevant and important aspects. In traditional methods, the focus is just on tangible monetary criteria. Also in the traditional methods, either all the information’s about factors must be known precisely or sufficient objective data must be available for applying probability theory. In this paper, a combinative approach is employed to integrate all monetary factors, subjective non monetary factors and also objective non monetary factors in decision making process of project evaluation and selection. In the proposed approach to deal with uncertainty in monetary criteria and also vagueness of human thought in subjective non monetary criteria, fuzzy cash flow analysis and multi criteria decision making method are applied, respectively. As a case study, this methodology has been applied for evaluation of an Iranian auto manufacturer’s projects. The results depict that the methodology can vastly help decision makers to evaluate projects under vague and uncertain circumstances considering all important criteria.