Abstrak
This study aims to determine the effect of the transformational leadership style on affective commitment, transformational leadership style on organizational citizenship behavior, affective commitment on organizational citizenship behavior, and transformational leadership style on organizational citizenship behavior mediated by employee’s affective commitment in the Bank Muamalat Indonesia (BMI) Padang Branch. This research was conducted at Bank Muamalat Indonesia Padang Branch. The questionnaires were distributed to collect data and analyzed using Regression analysis. The result of the analysis showed that a significant influence of transformational leadership style on employee’s affective commitment, transformational leadership style on employee’s organizational citizenship behavior, affective commitment on organizational citizenship behavior, and transformational leadership style on organizational citizenship behavior mediated by employee’s affective commitment in the BMI Padang Branch. Research findings contribute to the development of human resources to improve the performance of company employees.