Primary biliary cirrhosis (PBC) is an autoimmune disease of the liver frequently associated with extrahepatic autoimmune phenomena. Specific antibodies against platelet glycoproteins may play an important role in the pathogenesis of thrombocytopenia associated with PBC. This is the first report of life-threatening idiopathic thrombocytopenic purpura successfully treated with steroids in a 62-yr-old woman 2 yr after liver transplantation for PBC.