Formal education is an education system that is structured and based on a certain curriculum. The quality of education depends on the quality of teachers in teaching. As one of the formal faith-based education, Darullughah Wadda'wah Raci Bangil Foundation is an Islamic boarding school educational institution. Teacher performance in Islamic boarding schools is influenced by many things, some of which are the work environment, Islamic leadership style, and motivation considering that Islamic boarding schools are formal Islamic faith-based education. This study aims to provide empirical evidence on the effect of work environment, and Islamic leadership style on the performance of teachers mediated by work motivation at Darullughah Wadda'wah Raci Bangil Foundation. The subjects of this study were educators both permanent and contract employees within the Darullughah Wadda'wah Raci Bangil Foundation as many as 97 people used stamped thoroughly because the population was less than 100 or by census method. Primary data are the type of data that was utilized derived from questionnaire results distributed to respondents online, while data analysis uses path analysis. The results showed that the work environment and Islamic leadership style had a significant effect on teacher performance and the work environment and leadership style had a significant effect on work motivation. In this study, it was also explained that motivation influences teacher performance as well as can mediate the influence of the work environment and leadership style on teacher performance.