Ion: The improvement of teacher's performance is strongly influenced by the role of principal as supervisor through academic supervision. This study was aimed at determining the academic supervision program of principal in improving teacher performance, implementing academic supervision program in improving teacher performance, and following up the principal academic supervision in improving teacher performance. This research used qualitative approach. The result showed that: (1) the preparation of academic supervision program was compiled at the beginning of the school year by involving the teachers. Academic supervision program was compiled based on the program faced by the teachers in learning process and adjusted to the needs of teacher, and (2) the implementation of academic supervision was based on the program that have been prepared by using several techniques such individual and group, and (3) the follow-up was conducted by the principal by giving guidance to teachers who have not met the standars and by giving reward to teachers who have met the standard. Based on the result, the implementation of academic supervision of the principal in improving teachers's performance at MIN 2 of Takengon, Aceh Tengah regency has not done well.