Autoimmune hepatitis is a rare cause of chronic hepatitis in Korea. The cause of autoimmune hepatitis is unknown. A loss of tolerance to autologous liver tissue is regarded as the primary pathogenetic mechanism. The clinical course of this disease is slowly progressive. The clinical picture of autoimmune hepatitis is also often associated with extrapehatic disease, many of which have a presumed autoimmune origin. Untreated patients have a poor prognosis, however immunosuppressive treatment prolongs survival.