This study aims to evaluate the perception of teachers, who have the mission of leading to and developing of students, about their own leadership behaviors and self-development level. In this context, a total of 305 teachers, 235 in state secondary schools and 70 in private secondary schools in Trabzon province, were involved into the study. During the collection of the data, "Teacher Leadership Scale" and "Self-Development Scale" were used. The results of the study showed that teachers' perceptions of their own leadership behaviors and level of self-development were evaluated in most of the time intervals, and there was a meaningful difference in leadership behaviors in favor of private school teachers and in self-development behaviors in favor of female teachers. When the relationship between teachers' perceptions about their own leadership behaviors and self-development level was examined, weak associations in positive direction were found. In the regression analysis, it was observed that teacher leadership scale score increased as self-development scale score increased, and the total scores of the self-development scale and school type had a statistically meaningful effect on the teacher leadership scale. As a result of the research, it is suggested to select teachers for the profession who seek the ways for professional development and have leadership skills, provide trainings to teachers in these areas, and make changes in the curricula of the faculty of education to encourage teacher development and leadership.