Serum samples were available from 492 of 1,058 cadavers seen at the Philadelphia Medical Examiner's Office between August 4 and December 15, 1989. These sera were tested for the presence of antibodies to human immunodeficiency virus (HIV) by enzyme-linked immunosorbent assay (ELISA) and Western blot. The overall prevalence of HIV in the autopsy population was 2.24%. The following populations showed increased prevalence as compared to the total sampled population: blacks (3.60%, p less than 0.01), males (2.51%, n.s.), and homicide victims (3.74%, n.s.). Seroprevalence data from this study are compared with those from earlier studies of other related populations, with regard to overall prevalence and risk factor analysis.