The disease known as neurofibromatosis is now recognized to consist of distinct variants that differ from each other genetically, microscopically, and clinically. Neurofibromatosis type I (NF-I) is often referred to as von Recklinghausen's disease of skin, and its features are well known. Neurofibromatosis type II (NF-II) is a much more uncommon manifestation that probably results from a structural defect in chromosome 22, as opposed to NF-I, which is related to chromosome 17. Although neurofibromas occur in NF-II, neurilemmomas and acoustic neuromas are the predominant neural tumors; bilateral acoustic neuromas are the hallmark of the disease. NF-II largely afflicts the central nervous system and has a more gradual onset than and different clinical features from NF-I. One case each of NF-I and NF-II is presented, with emphasis on oral manifestations. Diagnostic techniques, treatment, and prognosis are reviewed.