Many studies have been done in the developed countries due to the importance of job satisfaction; however, only a limited number of studies have been conducted on teachers’ job satisfaction in Iran. This study is an attempt to investigate the relationship between teachers’ job satisfaction and their attitudes towards students’ beliefs and motivation.To this end, both qualitative and quantitative research methods including interview protocols and questionnaire were utilized. To collect data, in the quantitative part of the study, a validated questionnaire was administered to sample of 340 among the English teachers, teaching in Iranian language institutes in Isfahan. After gathering the questionnaires, those teachers willing to be interviewed were selected for in-depth interview. Both quantitative and qualitative data were categorized, coded and analyzed based upon the main themes and the respective research questions. The results revealed that there are empirically positive significant relationships (t > 2.56, P < 0.001) between teachers’ job satisfaction and their attitudes toward students’ motivation and beliefs. Moreover, the interviews showed that teachers’ level ofjob satisfaction was high, although they are not satisfied with financial matters. The finding can shed more light on the area of teachers’ job satisfaction and related factors to have better understanding of the relationship between job satisfaction and job performance. Furthermore, educational institutions through considering the results of the study can improve teachers’ perceptions of their job and improve job environment to manage language learning institutes or schools better than before.