The main purpose of this study is to examine the relationship between teachers' perceptions of supervisor support and job performances and the mediating role of job satisfaction in this relationship. The study group consists of 206 teachers working in the public high schools in the Giresun province centre during the 2016-2017 academic year. The study group has been determined by simple randomized sampling method. In the study, the effect of teachers' supervisor support perceptions on job performance and the mediating role of job satisfaction have been tested by forming a structural equation model. According to the results, there is a positive linear relationship between supervisor support, job performance and job satisfaction and job satisfaction has a full mediating role between supervisor support and job performance.