This study aims to examine and analyze the role of principal supervision in moderating the effect of professional competence and work discipline on teacher performance at the Sultan Agung Waqf Foundation, Semarang City. This type of research is explanatory. The population of this research is teachers at the Sultan Agung Waqf Foundation, Semarang City, with the status of permanent employees. Respondents in this study were 101 respondents. The data analysis technique used is moderation regression analysis. The results showed that professional competence and work discipline had a positive effect on teacher performance, while the supervision of the principal has negative effect on teacher performance at the Sultan Agung Waqf Foundation Senior High School, Semarang City. Supervision of school principals moderates the effect of professional competence on teacher performance at the Sultan Agung Waqf Foundation Senior High School, Semarang City. Supervision of the principal does not moderate the influence of discipline on teacher performance at the Sultan Agung Waqf Foundation Senior High School, Semarang City.

Keywords: Principal Supervision; Professional Competence; Work Discipline; Performance