Adult onset Still's disease (AOSD) is a rare systemic inflammatory disorder of unknown etiology and pathogenesis. The disease is characterized by typical spiking fever with evanescent rash, sore throat, polyarthralgias or polyarthritis, and involvement of various organs. Most of the reported cases with liver involvement occurred during the period of treatment with hepatotoxic drugs, whereas AOSD associated autoimmune hepatitis (AIH) is extremely rare. AIH may be an indicator of the poor prognosis of AOSD. Herein we describe a case of successful treatment with plasma exchange for AOSD-associated AIH.