Hidradenitis suppurativa (HS) is a cicatrizing, inflammatory and recurrent disease restricted to inverse skin, such as that of the axilla and groin of younger adults. In a previous study, using serological tissue-typing techniques, no significant increases in the human leukocyte antigen (HLA)-A and -B specificities were found in patients with HS. The aim of this study was to determine the frequencies of HLA-A, -B and, for the first time, HLA-DR alleles, using genomic tissue-typing methods in patients with HS. Forty-two unrelated Swedish patients with HS were included and compared with 250 controls. According to clinical staging adopted from Hurley all of the patients had stage II HS, i.e. recurrent abscesses with tract formation and cicatrization and single or multiple widely separated lesions. No association with HLA-A, -B or -DRB1 alleles was found in patients with HS. Genetic factors associated with the HLA class I or II regions do not appear to contribute significantly to the possible genetic susceptibility of HS.