OBJECTIVE To investigate the mechanism underlying the development of chronic hepatitis B virus infection (HBV) in Turkish population using HLA tissue typing. METHODS The study group I consisted of 20 patients with HBV-related chronic liver disease (cirrhosis, chronic active hepatitis or chronic persistent hepatitis). The study group II included 30 HBV chronic carriers. The control group consisted of 50 healthy subjects with negative serologic markers for HBV. HLA typing was performed by Terasaki's microlymphocytotoxicity method. RESULTS The frequencies of HLA-DR13 and DQ3 were significantly higher in the patients with HBV-related chronic liver disease compared to those of control group. The absence of HLA-A24 and CW1 was also significant in group I. The frequencies of HLA A2, B8, B13, CW3, DR13 were significantly higher in group II compared to the control group. There were increased frequencies of HLA- B8, B13, DR7, DR13, and DQ3 in both group I and group II. CONCLUSIONS HLA-A24 AND Cw1 were associated with low risk for HBV-related chronic liver disease and HLA- B13, B8, DR7, DR13 and DQ3 were associated with high risk for chronic HBV infection in the Turkish population (JPMA 52:253;2002).