Since the internal audit of the company is essential to supply information needed for the effective management and improvement of the competitive position, the purpose of this paper is to introduce an innovative strategic management tool for the assessment of internal organizational factors that overcomes some limitations of traditional appraisal methods, and also enables more comprehensive evaluation of the company’s internal environment. Although the classical Internal Factor Evaluation matrix (IFE matrix) is widely used, it has some constraints, such are lack of considering the ambiguity and vagueness of the internal factors. An original method – FSIF (Fuzzy Synthesis of Internal Factors) represents a systematic approach that incorporates fuzzy logic in order to better describe real situation. Proposed FSIF method well serves the needs of modern Management information system because it provides monitoring of internal development of an organization through time and also comparing different organizations taking into account various factors and weights.