Job satisfaction and individual and environmental factors affecting it, are the most important issues in the organizations because of their direct contact with human capital. Hence, evaluation the effect of individual and environmental factors on job satisfaction of employees in District 18 of Tehran municipality is the main purpose of this research. This is an applied research and data collection did through descriptive survey method. In order to collect primary data, a questionnaire package was used that included 34 questions in Likert scale. Validity of questionnaire was face validity and content validity and Cronbach's alpha coefficient was calculated to assess the reliability that was Equal to 0.881 for pre-test and 0.889 for post-test. The population of the study was all the staff of District 18 of Tehran municipality and 300 questionnaires were distributed among them by Stratified random manner. To do this research, two main hypotheses were developed and analyzed in two ways of descriptive and inferential statistics. In the descriptive analysis, the parameters of frequency, percentage, mean were used and to test the hypothesis of independence of the Chi-square test, Pearson correlation and regression analysis were used. The results show a significant positive correlation between environmental factors and job satisfaction there. This data shows that the average job satisfaction of employees is 3.48 and average satisfaction of individual factors and environmental Respectively is equal to 3.77 and 3.14. The results show that individual factors situation is quite adequate, so take action to improve the environment factors is a priority.