To determine the association of HLA antigens with SLE and the clinical findings of the disease, HLA antigens were tested in 58 Japanese patients with SLE, who fulfilled the ARA diagnostic criteria, along with 97 normal controls. HLA class I and II antigens were typed serologically using the antisera provided by the 11th HLA Workshop. Among the HLA class II antigens, further DRB, DQ and DP alleles were defined by DNA typing using the PCR/SSOP method. There were significantly more SLE patients with HLA-B39, DRB1*1501, DRB5*0101 and DQB1*0602 than normal controls. This result suggested that the haplotype of HLA-DRB1*1501-DRB5*0101-DQA1*0102-DQB1*0602 consists of the SLE-associated MHC markers in Japan. There were some positive and negative associations between the HLA antigens and clinical or serological findings in SLE. There is a possibility that some HLA alleles might be related to the clinical and/or serological subsets of SLE.