This study aims to determine the effect of Work Discipline, Work Facilities and Mastery of Technology on the Performance of Public Elementary School Teachers in Kemangkon District, Purbalingga Regency. The sample used in this study was a public elementary school teacher in Kemangkon sub-district, Purbalingga district, consisting of 150 respondents using a random sampling technique. The analysis used is multiple linear regression. The results of this study state that Work Discipline, Work Facilities and Mastery of Technology simultaneously have a significant effect on teacher performance. Based on the t test results obtained; (1) Work Discipline has a positive and significant effect on teacher performance. (2) Work facilities have no effect on teacher performance. (3) Mastery of Technology has no effect on teacher performance. Based on the results of the R2 adjusted coefficient of determination test, it shows that the influence of Work Discipline, Work Facilities and Mastery of Technology on Teacher Performance is 20.9%, while the remaining 79.1% is influenced by other variables not examined.