This study explored the effect of managerial power on employees' affective commitment using social exchange theory. It was applicable-descriptive and the research sample included 185 managers of the Social Security Organization of Fars Province. The required data was collected via a researcher self-made questionnaire that consisted of two sections of managerial power and affective commitment. Validity of the questionnaire was confirmed by five professors and its reliability was obtained equal to 0.89 via Cronbach's alpha coefficient. The data was analyzed through Amos19 and EQS6.1 software. Two important findings were obtained. First, there was a positive and significant relationship between expert power, legitimate power, referent power, reward power and coercive power with affective commitment. Second, reward power had the highest effect and coercive power had the lowest effect on employees' affective commitment. The findings revealed that desirable perceptions of employees from the manager's power in the framework of social exchange will lead to positive consequences such as affective commitment.