The purpose of this study is to investigate the research trend of teacher leadership and suggest the directions and tasks. To achieve the goal, the features of teacher leadership were drawn from literature review. Based on the features, total 27 of doctoral dissertations and academic articles were analyzed to find the research trend. Major findings of this study were as follows. First, teacher leadership was characterised by a variety of formal and informal grouping. Second, most of previous research focused on the ‘students’, ‘teachers’ , ‘task-oriented’ and ‘collegiality’, whereas little research to date has inquired about ‘school administrators’, ‘parents’ and ‘goal-oriented’. Third, it needs to conduct studies related to all fields of teacher leadership, make an effort to study the research trend of teacher leadership, and seek the practical model for teacher leadership development programs.