Background/Aims: Hepatitis virus and alcohol are two of the most common causes of chronic liver disease in Korea. However, autoimmune hepatitis (AIH) has been reported sporadically. We determined the clinical and laboratory features of AIH. Methods: For 14 patients diagnosed as having AIH in our hospital since 1991, we reviewed medical records and analyzed clinical and laboratory findings retrospectively. They had a probable or definite AIH according to the revised criteria of International AIH group. Results: The mean age was 47.1 (26-61) years and 12 (85.7%) were female. Ten of them (71.4%) showed acute onset and their serum bilirubin level was 16.9±8.1 mg/dl. Fatigue and anorexia were the most frequently complained symptoms (92.8% and 64.2%). Seven patients (50%) were accompanied with other autoimmune diseases. Antinuclear antibody was detected in 10 (71.4%) and anti-smooth muscle antibody was detected in 7 (63.6%). There were no significant differences in clinical and laboratory findings between type 1 AIH and other subtypes of AIH. Among 12 patients who received immunosuppressants, complete remission was achieved in 5 but 7 had a relapse. Conclusions: AIH should be suspected in diagnosing chronic liver disease of unknown etiology, especially in female patients. The clinical characteristics of AIH may not be quite different from those of Western countries. (Korean J Gastroenterol 2001;37:362-369)