BACKGROUND: An estimated 150 million people worldwide are infected with hepatitis C virus (HCV). HIV co-infection accelerates the progression of HCV and represents a major public health challenge. We aimed to determine the epidemiology of HCV and the prevalence of HIV co-infection in sub-Saharan Africa. METHODS: We searched Medline and Embase (Ovid) from Jan 1, 2002, to Dec 31, 2014, for studies containing data for HCV seroprevalence in different population groups in WHO-defined regions of sub-Saharan Africa. We estimated pooled regional prevalence estimates with a DerSimonian-Laird random-effects model. Data were further stratified by risk factor and HIV status. FINDINGS: We included 213 studies from 33 countries in sub-Saharan Africa, comprising 287 separate cohorts with 1 198 167 individuals. The pooled HCV seroprevalence from all cohorts was 2.98% (95% CI 2.86-3.10). The pooled HCV seroprevalence was 2.65% (95% CI 2.53-2.78) across all 185 low-risk cohorts, 3.04% (2.23-3.84) in antenatal clinic groups, 1.99% (1.86-2.12) in blood donors, but 6.9% (6.1-7.5) in other general population cohorts. The pooled seroprevalence of HCV was 11.87% (95% CI 7.05-16.70) across all high-risk groups and 9.95% (6.79-13.11) in patients with liver disease. 101 cohorts included HIV-positive samples tested for HCV (42 648 individuals), with a pooled seroprevalence of 5.73% (95% CI 4.90-6.56). INTERPRETATION: We recorded a high seroprevalence of HCV across populations of sub-Saharan Africa, including in HIV-positive adults, with evidence of regional variation in the general population. Monitoring of antenatal HCV prevalence might be a helpful indicator of population trends in HCV infection; however, larger population surveys are needed to monitor these trends. Access to prevention and treatment needs to be improved for both monoinfected and co-infected individuals. FUNDING: None.