This study is aimed to explore the structural relationships among the factors affecting the employees' voice. In this regard, by reviewing the literature, a set of factors influencing the occurrence of organizational voice was identified. Then the opinions of 15 senior and middle managers and academic professors about the relationship between these factors were examined. Finally, data were analyzed by utilizing the Interpretive Structural Modeling (ISM) and Fuzzy MICMAC methods. According to results, organizational culture has an underlying role in organizational voice. In fact, it can be said that existence of an ideal organizational culture can be reflected in the improvement of employees’ knowledge, understanding about the organization, awareness and their experiences. These factors also increase the psychological safety and eventually, their self-confidence. Moreover, employees’ self-confidence also influences the willingness of organization for accepting and valuing their voice, their change commitment, job satisfaction and openness to experience. Finally, these factors in an interaction to each other, increase the employees’ courage to express their ideas. As a general result, this research showed that the appearance of organizational voice is a sign of existence of an organization's desirable culture.