The case in which patients present clinical, biological, and histological features of both primary bil iary cirrhosis (PBC) and autoimmune hepatitis (AIH) is rare. Such overlap syndrome is believed to be associated with a poor prognosis. We report a case of PBC-AIH overlap syndrome associated with IgA nephropathy. The patient showed hepatitic and nephritic features including easy fatigability, pruritus, icteric sclera and gross hematuria. The liver biopsy showed chronic hepatitis with piecemea necrosis and bridging necrosis. The clinical data of high titers of antinuclear antibodies and antimi tochondrial antibodies, elevated serum IgM and recurrent pruritus, suggest mixed features of AIH and PBC. IgA nephropathy was confirmed by renal biopsy. High dose of corticosteroids was effective initially, but clinical symptoms were relapsed after tapering the administration of corticosteroids. Thus, azathioprine was administered at a dose of 2 mg/kg/day. A dramatic improvement was noted in clinical conditions and liver tests.