A survey was conducted among residents aged 25-55 years in randomly selected villages with many former blood/plasma donors. Among the 1997 participants, the prevalence of HIV was 10.8%. The proportion reporting multiple sexual partners was 3.1%. Being male, younger, having other jobs, lower income, a positive attitude towards HIV-positives having sex, and being HIV-positive were associated with multiple partners. Most boyfriends/girlfriends were from local areas (87.5%). Two-thirds of the sex workers visited by HIV-positives were in urban areas. Within marriage, consistent condom use was only 1.1%. Only 0.5% used condoms with girlfriends/boyfriends, but 23.5% of men used condoms with sex workers. Therefore, HIV-infected villagers are spreading HIV within local and urban areas. Promotion of condoms with all partners and limiting sexual partners are urgently needed to reduce the spread of HIV. Intervention programmes should promote HIV/AIDS education, consistent condom use, and voluntary counselling and testing.