This study was conducted to examine the direct association as well as interactive (moderating) association of job characteristics (skill variety, task identity, task significance, autonomy and feedback) and Person-organization fit with job satisfaction. In this study, mean differences in level of job satisfaction within and among different demographic variables also were examined. Responses were collected from 157 employees working in 31 INGOs in Nepal. Deductive reasoning approach and quantitative analysis has been used to infer conclusion. This study concluded that: level of employee's job satisfaction was very high, mean differences in job satisfaction within demographic groups were significant as well as insignificant. Job characteristics and Person-organization fit were positively associated with job satisfaction. Person-organization fit did not moderate the relationship between job characteristics and job satisfaction.