Based on the question of the pros and cons of the problem due to the expansion of the internal-type openly recruited school principal, the purpose of this study is to understand the leadership characteristics of the internal-type openly recruited school principal who does not have the principal s certificate and explore where such leadership came from. The subjects of the study were one internal-type openly recruited school principal who does not have the principal s certificate and three teachers who have worked at the school. The data collected through in-depth interviews were analyzed using Stake s (1995) Direct interpretation and open coding method, based on leadership theory and power base theory. The results of the study are as follows: Principal A decided to enroll an internal-type openly recruited school principal based on his accountabilities as a senior teacher, his experiences in implementing the school community, and his confidence in life as a teacher through the practice of teaching and guidance. Even after becoming the principal, he turned the senior teachers meeting into a reading debate group, established all the members of the school as the main body to realize the sustainability and educational philosophy of the school organization, and formed the school community through respect and consideration. In addition, class instruction and guidance were respected as senior teachers by junior teaching teachers. Through this process, the leadership of the principal A is characterized as follows. Principal A acts as a leader to form a school community and make the members of education themselves and was recognized by the members of education through expert power due to instructional leadership. The principal s leadership has been nurtured and developed since the time of teachers. This study is meaningful in that it empirically examines the realization of what the leadership of the principal of the internal-type openly recruited school principal is, who does not have the principal s certificate, which is at the center of the controversy.