Few prospective studies have evaluated the association between alcohol use and STI acquisition among African women. We examined the association between baseline drinking frequency and STIs in a cohort of Kenyan women reporting transactional sex. The association between alcohol use and STI differed significantly by HIV status. Among 139 HIV-positive women, STI acquisition was significantly associated with consuming 1–7 drinks/week and marginally associated with ≥8 drinks/week in unadjusted analyses. However, no association between alcohol use and STIs was observed among 335 HIV-negative women. Addressing alcohol use within comprehensive HIV care may also reduce the burden of STIs among high-risk women.