External auditory canal cholesteatoma is an uncommon lesion of the external auditory canal, which usually present with otorrhea and chronic dull pain. It usually eroded bony portion of external auditory canal wall extensively with progressive bony lysis, and can extends into the middle ear cavity, tegmen tympani, mastoid air cells, and/or skull base. External auditory canal cholesteatoma invading skull base is rare, and such a case is not yet reported in Korea. We experienced one case of bilateral external auditory canal cholesteatoma invading the dura of middle cranial fossa which was treated surgically by the endoaural approach in right side and the middle cranial fossa /transmeatal combined approach in left side. We present this case with a review of the literature