In this brief review, the use of synthetic peptides representing linear antigenic sites in human immunodeficiency virus (HIV) structural proteins for detection of antibodies in sera from HIV-infected individuals is discussed. It has been demonstrated that peptide antigens offer unique advantages for determination of HIV-specific antibodies. In particular, various peptides representing the region of amino acids 580–620 in the transmembranous glycoprotein have been effectively used. Of primary importance is the fact that properly designed site-specific serological tests allow a distinction between type-specific antibodies, a quality not provided by any other currently available test. Furthermore, synthetic peptide antigens allow the design of highly simplified and effectively standardized assays. Hereby, they lend themselves to use for screening purposes or confirmatory testings not only in industrialized countries, but also in developing countries. It is also possible that tests with selected peptides may measure antibodies which have value in predicting the risk for infection in children born to seropositive mothers and for progression of disease in infected individual