Background: Although domestic HIV/AIDS financing is increasing, international HIV/AIDS financing has plateaued. Providing incentives for the health system (i.e. performance-based financing [PBF]) may help countries achieve more with available resources. We systematically reviewed effects of PBF on HIV/AIDS service delivery to inform WHO guidelines. Methods: PubMed, WHO Index Medicus, conference databases, and clinical trial registries were searched in April 2015 for randomised trials, comparative contemporaneous studies, or time-series studies. Studies evaluating PBF in people with HIV were included when they reported service quality, access, or cost. Meta-analyses were not possible due to limited data. This study is registered with PROSPERO, number CRD42015023207. Results: Four studies, published from 2009 to 2015 and including 173,262 people, met the eligibility criteria. All studies were from Sub-Saharan Africa. PBF did not improve individual testing coverage (relative risk [RR], 1.00, 95% confidence interval [CI] 0.89 to 1.13), improved couples testing coverage (RR 1.11, 95% CI 1.02 to 1.20), and improved pregnant women testing coverage (RR 1.29, 95% CI 1.28-1.30). PBF improved coverage of antiretrovirals in pregnant women (RR 1.55, 95% CI 1.50 to 1.59), infants (RR 1.92, 95% CI 1.84 to 2.01), and adults (RR 1.74, 1.64 to 1.85). PBF reduced attrition (RR 0.84, 95% CI 0.74 to 0.96) and treatment failure (odds ratio 0.55, 95% CI 0.32 to 0.97). Potential harms were not reported. Conclusions: Although the limited data suggests PBF positively affected HIV service access and quality, critical health system and governance knowledge gaps remain. More research is needed to inform national policymaking.