The purpose of this study was to determine the relationship between transformational\ transactional leadership styles and organizational citizenship behavior in Physical Education Organization of Iran and which dimensions of these styles enhanced organizational citizenship behaviors of employees. The population of this study consisted of 273 employees of Physical Education Organization; 220 employees completed the questionnaire who consisted the sample of the study. The employees were required to complete Multifactor Leadership Questionnaire (Bass & Avolio 2000) and Organizational Citizenship Behavior Scale (Podsakoff et al. 1990). The validity and reliability coefficients of the questionnaires were calculated. The findings indicated that transformational leadership style and organizational citizenship behavior were moderate. There was a significant relationship between transformational\ transactional leadership styles and organizational citizenship behavior. Multiple regression analysis indicated that transformational leadership style was a stronger predictor of organizational citizenship behavior. Structural Equation Modeling (SEM) indicated that transformational leadership style had more effect on organizational citizenship behavior. It is recommended that managers use transformational leadership style.