The purpose of this study is to find out the factors that create job stress and their impact on job performance among the teachers of private educational sector. The independent variables of this study are workload, work environment and monetary rewards and the dependent variable is job performance. A survey has been conducted with 200 respondents.The Questionnaire is used after pilot testing in order to accomplish the desired objective with the help of respondents’ responses. Test technique that is applied ismultiple regression analysis and ANOVA analysis. This paper attempts to identify the determinants of job stress and its impact on job performance.The analyses of data showed that excessive workload, negative work environment and in sufficient monetary rewards have significant impact on job performance. The results of regression supports the hypothesis that excessive workload, negative environment and insufficient monetary rewards affect the job performance of teachers at work