We report the results of the epidemiological and serological studies concerning HIV-1 and HIV-2 infections carried out in a group of 203 seamen who visited the sub-Saharan area (west coast of Africa). The following risky practices were detected: history of drugs abuse 8 (3.9%), transfusion 3 (1.5%), use of parenteral medicines in Africa 80 (39.4%), surgery in Africa 41 (20%), tattoos 18 (8.9%). Sexual behavior: stable couple 180 (88.7%), number of sexual couples 4.2 +/- 6, contacts with prostitutes 108 (53%), contacts with prostitutes in Africa 83 (40.9%), others heterosexual contacts 58 (28.6%), homosexual 1 (0.5%), history of VD 34 (16.7%), 94% of the seamen never (or occasionally) used the preservative with theirs couples and 73% of them didn't use it with others contacts. Four seamen were HIV-1 (+): contacts with prostitutes in Africa 2, use of parenteral medicines in Africa 1 and drugs abuse 1. We observed a high prevalence of risky practices associated with HIV-1 infection between seamen population. It is interesting to remark the importance of heterosexual transmission and the use of parenteral medicines.