Résumé : Objectives. To determine the impact of the mode of recruitment of blood donors on the prevalence of blood-borne infections (HIV and HBV). Methodology. Retrospective cohort study, conducted in Bukavu (eastern DR Congo) 2001-2005. HBsAg and HIV tests were analyzed according to age, sex, type, and category of donors. Proportions were compared with Pearson Chi2 or Fisher's exact tests and Chi2 trend tests, and the strength of associations measured by odds ratios (and their 95% CI). Results. Men accounted for 70.2% of the donors, and 88.3% were volunteers (n = 3292). Regular donors (n = 7442) provided 75% of the donations. The proportion of family donors decreased over time, from 14.3% in 2001 to 5.1% in 2005. HIV prevalence was 1% and that of HBsAg 3.7%. Prevalence rates were higher among new donors than among regular donors (HIV 1.9% versus 0.2% and HBsAg 7.3% versus 0.5%), among family donors than among volunteers (4.2% versus 1.6% for HIV and 9.9% versus 7% for HBs Ag, and among women than among men (2.8% versus 1.6%, OR = 1.79 [1.08-2.96]). Thus new women family donors were 3.75 times more likely to be HIV-positive as new volunteers who were women (OR = 3.75 [1.65-8.55]). The prevalence of HBsAg among new women donors was 5.8%, lower than among their male counterparts, 7.9% (OR = 0.71 [0.51-0.98]). Conclusion. Risk of contamination by seropositive donors was lowest for regular and volunteer blood donors.