There is a potentially high risk of HIV spreading from people living with HIV/AIDS. We conducted a cross-sectional study to examine HIV risk behaviours and their determinants among people living with HIV/AIDS. Eighty-two percent had been sexually active. Sex with multiple partners was reported by 20% and consistent condom use by about one third. More than half of the participants (52%) reported having injected drugs during the previous month, and 35% of those had shared needles and syringes. Voluntary HIV testing and having received condoms or injection equipment from the local HIV prevention program, were found to be significantly associated with fewer HIV risk behaviours. Having learned recently about personal HIV status, multiple sex partners, low educational attainment and young age were found to be associated with higher HIV risk behaviours. Giving high priority to targeted preventive and support programmes is likely to be a highly cost-effective strategy.