This study aims to determine the influence of the principal's supervisory competence and school culture on Teachers Performance of Public High School in Kutai Kartanegara Regency. The sample of this study amounted to 118 teachers. Data collection techniques used survey method with data analysis using descriptive statistics and inferential statistics. Data analysis descriptively obtained the average score of principal supervision competence 163,73, the average score of school culture 161,81; and the average teacher performance score of 169.99 in which the three variables fall into the medium category. The result of inferential analysis using multiple linear regression with 5% significant level shows improvement of one unit of principal supervision competence can cause teacher performance improvement equal to 0,14 unit value at constant 89,39 and one school culture unit can cause teacher performance improvement equal to 0,36 at constant 89.39. The conclusions of this study indicate that there is an influence between the principal's supervision competence and school culture on teacher performance. In other words, the higher the supervisory competence of the school principal and the school culture shows the better the performance of the teacher