In a cross-sectional study, monocyte subsets in placental, cord, and maternal peripheral blood from pregnant Malawian women with human immunodeficiency virus (HIV)-1 infection and/or malaria were analyzed. HIV-uninfected Malawian women had higher baseline proportions of CD16⁺ monocytes than those reported for healthy adults in developed countries. Malaria was associated with an increase in the proportion of CD16⁺ monocytes that was significant in women coinfected with HIV-1. CD16⁺ monocytes expressed higher CCR5 levels than did CD14^hi/CD16⁻ monocytes and were significantly more likely to harbor HIV-1. These data suggest a role for CD16⁺ monocytes in the pathogenesis of maternal malaria and HIV-1 infections.