While research on the role of employees’ characteristics as core to transformational leadership theory is burgeoning, limited research has focused on the differing aspects of employees’ self-determined motivation as mediating mechanism through which transformational leadership may impact outcomes. Drawing on the self-determined theory of motivation, we build and test a theoretical model linking employees’ perceptions of transformational leadership with engagement through an intervening variable of differing aspects of employees’ self-determined motivation. Data from a sample of 155 participants revealed that employees’ perceptions of transformational leadership were positively related to employees’ self-determined motivation (intrinsic, autonomous, and controlled) and work engagement. Specifically, self-determined motivation (intrinsic, autonomous) was positively linked with work engagement while intrinsic, autonomous and controlled dimensions of self-determined motivation mediated the relationship between transformational leadership and work engagement. We discuss the theoretical and practical implications of the results.