The smoking behaviour of persons living with HIV/AIDS in sub-Saharan Africa is poorly documented. We employed a cross-sectional study design to assess the prevalence and predictors of tobacco smoking among HIV-infected patients in northern Nigeria (n = 296). Approximately one quarter of respondents were either current (7.8%) or ex-smokers (17.9%). Smoking rates among HIV-infected women were extremely low. HIV-infected men were at least three times as likely to smoke as their female counterparts living with HIV: adjusted odds ratio (AOR) 3.16, 95% confidence interval (95% CI) 2.17-7.32. Patients with tertiary education were at least twice as likely to smoke compared with their counterparts without formal education (AOR 2.63, 95% CI 1.08-6.67). The preponderance of cigarette smoking among educated HIV-infected men in northern Nigeria offers a unique opportunity for targeted smoking cessation programmes.