The purpose of this study was to determine the effect of the principal's academic supervision on teacher performance at SMK Negeri 2 Siatas Barita in 2023. The method used in this research is quantitative research method. The population is all teachers at SMK Negeri 2 Siatas Barita with a total of 64 teachers and this research is a population study. Data were collected with a positive closed questionnaire of 46 items. The results of data analysis show that there is an influence of the principal's academic supervision on teacher performance at SMK Negeri 2 Siatas Barita in 2023. 1) Test of analysis requirements: a) positive influence test obtained rxy value = 0.486 > r table (α = 0.05, n = 64) = 0.244 thus it is known that there is a positive influence between variable X and variable Y. b) significant relationship test obtained tcount = 4.380 > t table (α = 0.05, dk = n-2 = 62) = 2.000 thus there is a significant relationship between variable X and variable Y. 2) Effect test: a) Regression equation test, obtained regression equation Y ̂ = 53.452 + 0.278X. b) Regression determination coefficient test (r2) = 23.6%. 3) Hypothesis testing using the F test obtained Fcount> Ftable, namely 19.188> 4.00. Thus Ha is accepted and H0 is rejected.