ABSTRACT Many organizational and environmental factors affect the information disclosure and the quality of its presentation; organizational culture is the most important factor among these factors. The organizational culture that is based on transparency will provide the information environment dynamism and it will also lead to the improvement of the quality of information disclosure by the business units. This effect is more prominent especially in the countries such as Iran which has a variety of tribes and population groups with different cultures. In this regard, the aim of this study is to evaluate the impact of organizational culture on the voluntary disclosure in Iranian firms. The study of organizational culture of Iranian firms and its impact on the voluntary disclosure in 2015 has shown that the organizational culture that is based on involvement and consistency has a positive and significant impact on the voluntary disclosure of information. Also, the organizational culture based on a mission has an adverse impact on the voluntary disclosure. These results could be useful for the policies of the senior managers of Iranian firms in the field of organizational culture and they will also lead to the improvement of the implementation of accountability procedures. Also, by identifying and modifying the types of company's organizational culture, we can lead to the enhancement of the voluntary disclosure.
