To implement a second-generation HIV surveillance, through a prevention programme of HIV and sexually transmitted infections (STIs), Senegal conducted a combined survey from 2003 September 2 to October 5 in Malicounda located in the region of Thiès in the center of Senegal. The objectives of this study were to collect data on sexual behaviours and prevalence of HIV gonorrhoea, Chlamydia infections and syphilis in the community. After obtaining their informed consent, 679 people were interviewed among whom 617 accepted blood sampling and 619 accepted urine sampling, that is to say an acceptance rate of 90% and 91% respectively. Women reported having fewer sexual risk behaviours than men. However, when having sexual risk behaviour men only reported using condoms. Overall, the prevalence of HIV as well as the prevalence of STI are low: 0.5% for HIV, 0.9% for syphilis, 0.3% for Chlamydia trachomatis and 0.2% for Neisseria gonorrhoea. In this study, the small numbers of cases of infection identified did not allow to analyse the influence of sexual behaviour at risk on the occurrence of these infections.