ABSTRACT HELMI RUSTAM. Principal Leadership Strategies in Improving Teacher Professionalism. Case study in Madina Islamic School, South Jakarta. Thesis. Jakarta: Graduate Program of University of Muhammadiyah Prof. DR. Hamka, 2012. This study aims to determine the principal's leadership strategy in improving the professionalism of teachers in Madina Islamic School. This is a qualitative study, using a method of data collection such as: observation, interview, documentation and triangulation study. Conclusions in this study were (1) implementation of the strategy undertaken by the principal should be fully supported by the school stakeholders (2) leadership goes well, if the principal can use a type of democratic leadership for teachers and other stakeholders. They can work together in carrying out their duties and functions each other. (3) communication has an important role in the context of the relationship between principal and teachers. two-way communications is appropriately used in the context of leadership. (4) as the principal inspiration was asked to be the inspiration by teachers in a variety of things such as attitudes, performance. In this case the principal needs time to be the inspiration for teachers in Madina Islamic School. The findings in this study were (1) implementation of the strategy undertaken by the school principal there are still obstacles in the field that the principal has not received full support from management to some of the strategies implemented by the principal. (2) principal in carrying out its duties and functions in Madina Islamic School is still using authoritative leadership. Principal can not give full opportunity to do the tasks assigned by the principal. (3) one of the principal's leadership strategy in improving the professionalism of teachers in Madina Islamic School is how principal uses communication in interaction with teachers. In this case principal tends to use one-way communication. (4) In some cases the principal has been the inspiration by teachers. Personal relationships among principal and teachers still look stiff.