To characterize human immunodeficiency virus (HIV) risk practices among men with tuberculosis, and to determine what factors are associated with HIV infection in this population, we conducted a case-control analysis of data collected during enrollment in a prospective cohort study in the two large tuberculosis treatment centers of Abidjan, Côte d'Ivoire. Demographic information and data on risk factors for HIV infection, including history of sex with female sex workers (FSWs) and history of sexually transmitted diseases (STDs), were collected on 490 HIV-infected and 239 HIV-uninfected men diagnosed with pulmonary tuberculosis between 1989 and 1992. HIV-infected men were significantly more likely than uninfected men to have had sex with FSWs in their lifetime [83 versus 63%, odds ratio (OR) 2.9, 95% confidence internal (CI) 2.0-4.2], genital ulcer disease in the past 5 years (38 versus 15%, OR 3.4, 95% CI 2.2-5.2), urethritis in the past 5 years (44 versus 23%, OR 2.6, 95% CI 1.8-3.8), and sex with FSWs in the past year (43 versus 25%, OR 2.3, 95% CI 1.6-3.3); no difference was found in the proportion with at least one non-FSW partner in the past year (84 versus 79%, OR 1.3, 95% CI 0.9-2.0). Among all men, 74% never used condoms, and only 1.4% always used condoms. In a multivariate analysis, sex with FSWs, genital ulcer disease, urethritis, and lack of circumcision were all significantly associated with HIV. This study demonstrates the critical roles of commercial sex, STDs, and condom neglect in fueling the HIV/AIDS epidemic in Abidjan, and illustrates the urgent need for widespread HIV education both in the general population and in men with tuberculosis.