The Influence of Principal’s Leadership and Teacher’s Professionalism on Teacher’s Performance at Muhammadiyah Private Junior High School in Medan

This research discussed about the effect of principal’s leadership and teacher’s professionalism on teacher’s performance at Muhammadiyah Private Junior High School in Medan. The research method used is quantitative research with a path analysis approach which the population was 380 people and the total sample was 195 people by using the Harry King Nomogram. The sampling technique used proportional random sampling. The research respondents were teachers of Muhammadiyah Private Junior High School in Medan and 195 people as the sample. The data collection techniques used the Likert scale model instrument. Based on the research, it found that the influence of principal’s leadership on teacher’s performance was 0.164, the effect of professionalism on teacher’s performance was 0.178, and the influence of the principal’s leadership on teacher’s professionalism was 0.362. From the result, it shown that the influence of principal’s leadership and teacher’s professionalism had a significant effect on teacher’s performance. The efforts to improve teacher’s performance will be successful through improving the principal’s leadership and increasing teacher’s professionalism.