This study attempted to examine the characteristics of teachers who demonstrate teacher leadership in high schools in depth and explore the characteristics and meanings of teachers who demonstrate teacher leadership. Based on prior research and discussions by Kim, Byeong chan(2019), a qualitative case study was conducted to inductively derive the characteristics of teachers demonstrating teacher leadership using teacher leadership consciousness, teacher leadership competency, and teacher leadership properties. From July 2019 to October 2021, five to seven in-depth interviews were conducted with eight study participants with a data collection period of about two years and four months. As a result of the study, the characteristics of teachers demonstrating high schools teacher leadership are summarized as follows. First, the characteristics of teacher leadership consciousness were shown as ‘being an active agent’, ‘calling and commitment’, and ‘community solidarity’, and the the characteristics of teacher leadership competency were ‘relationship-oriented communication’, ‘promotion and assistance’, ‘cooperative problem solving’, and ‘continuous reflection and belief’. Finally, the characteristics of teacher leadership properties were ‘leading change’, ‘the formation of a trust community’, and ‘the leap of teacher expertise’. Taken together, the characteristics of teachers demonstrating teacher leadership are ‘sacrifice leadership for all’, realizing ‘real education, leadership for real schools’, and creating ’voluntary vitality leading to teacher efficacy’. The meaning of teacher leadership display teacher characteristics was firstly reinterpreted by the theory of leadership characteristics, secondly, expansion of targets and areas of teacher leadership exercise, and third, the interaction of teacher leadership consciousness, competency, and performance attributes. This study is meaningful in that it presented an academic direction for follow-up research on teacher leadership by closely examining the characteristics of teachers who demonstrate teacher leadership through qualitative research.