The study investigated the leadership styles of principals who were successful in achieving good results consistently in the Senior School Certificate Examination (SSCE) in Edo State, Nigeria. No previous studies have examined leadership styles and the link to student performance as measured by public examinations in Edo State. The transformational leadership model was used to conceptualize the leadership styles of principals in this study. It was hypothesized that there is a positive relationship between transformational leadership behaviors of principals and overall performance of students. Analysis of principals' leadership style was conducted using the transformational Multifactor Leadership Questionnaire 5X Short. The findings demonstrate support for the hypothesis relative to five dimensions of transformational leadership and student's performance in the SSCE. The study also shows that transformational leadership is an important element of school improvement. Hence, the findings have important implications for education professionals and administrators with respect to planning for leadership development and preparation of teachers in Edo State.