Rangers in the Democratic Republic of the Congo are working to conserve some of the largest remaining blocks of tropical rainforest, along with iconic species that are being targeted by poachers for subsistence or commercial purposes. During 2015–2016 we surveyed 72% of Kahuzi–Biega National Park rangers to assess their level of job satisfaction, why they chose to become rangers, what they liked and disliked about their job, and what affected their motivation to conduct their work. We used a cumulative link model to assess how various factors affected their self-reported level of job satisfaction. The rangers surveyed had been working in the Park for 16 years on average and most chose this occupation to earn a salary, to conserve wildlife or to serve their country. Overall, ranger job satisfaction was low; however, our findings highlight numerous ways in which this could be improved. These include higher salaries, more promotion opportunities, better recognition from the Congolese wildlife authority and other state services, positive performance incentives, better security, improved living conditions in remote patrol posts, and more support from the judicial system. Ranger patrol assignment (i.e. type of patrol and Park sector to patrol), receiving free housing at the Park headquarters, age, and length of service were statistically significant predictors of job satisfaction. It is likely that increasing ranger job satisfaction would result in a higher commitment to protecting wildlife, improved performance, and positive outcomes for wildlife conservation.