In the period 1988-1991 the HIV-1 antibody test was performed in a total of 389 autopsied drug addicts. The HIV-1 incidence rose from 6% in 1988 to 14% in 1990 and 14% in 1991. There was no significant difference between the cumulated incidence in males and females. The HIV-1-positive addicts were compared to the HIV-1 negative addicts as regards mean age, duration of abuse, residence and cause and manner of death. Except for residence, where significantly more HIV-1-positive than negative addicts lived in Copenhagen, there were no significant differences between the two groups. In about one-third of the HIV-1-positive cases, equal both for males and females, the HIV-1-positivity was not known beforehand. The results are discussed in relation to the findings in other countries and to the findings in selected groups of living addicts in Copenhagen. It is concluded, that the diagnosis of HIV-1 infection in autopsied drug addicts is important from epidemiologic and hygienic points of view.