The present research examined the determinants of private security officers' job satisfaction. Specifically, the impact of perceived citizen views and supervisor support on job satisfaction was explored while investigating the mediating effect of self-legitimacy. A convenience sample of South Korean private security officers were explored by using a paper-and-pencil questionnaire and in-depth interviews. The results showed that perceived citizen views and supervisor support positively affected self-legitimacy and job satisfaction, and self-legitimacy mediated the impact of perceived citizen views on job satisfaction. This research contributes to the job satisfaction and private security literature as no prior studies have assessed the influence of perceived citizen views, supervisor support, and self-legitimacy on the job satisfaction of private security officers. Policy implications and future research directions are discussed.