Inverted papilloma is characterized by its destructive capacity, high rate of recurrence and the possibility of association with malignancy. Medial maxillectomy has been emphasized as a treatment of choice, for conservative treatments resulted in higher recurrence rate. Recently, introduction, which made more precise evaluation of intranasal lesions possible. In this context, the role of conservative surgery using nasal endoscope in the treatment of inverted papilloma was evaluated. Eighteen patients diagnosed as inverted papilloma in Seoul National University Hospital have been operated by the first author during 8-year period beginning from 1987 through 1995. Seven patients were treated via external approach and eleven patients with conservative surgery. One patient recurred after endoscopic excision with Caldwell-Luc's operation, and treated again by endoscopic excision without recurrence. This study shows that inverted papilloma can be removed completely by endoscopic surgery in selected cases, resulting in comparable recurrence rate to more extensive type of surgery.