The main purpose of this research is to investigate how the principal in the case study uses his or her instructional leadership to promote the professional development of teacher(s). It was found that the principal's instructional leadership strategies include: Professional leadership, founded on learning and actual participation by the principal; the principal's action capability to create and display the vision; teaching observation; professional dialogue and group learning; and the participation of teacher leaders . Performances include: Creation of a learning atmosphere within the campus; the inspiration of teacher's professional perceptions; and care for the fulfillment of education quality through administrative and teaching methods. In the final part of this paper, four suggestions will be provided. First, the principal must start from the learning of self-leadership to reinforce personal value of education. Second, the principal and teachers must all take a serious look at the importance of professional development. Third, the principal should promote teacher's habits and capabilities for professional dialogues. Last, there are recommendations for future research.