Pathological examinations diagnosed in the Department of Oral Pathology of Iwate Medical University in 1997, were statistically reviewed.Atotal of 638 biopsies was discovered among 562 cases (Male:266, Female:296). The cases were found most frequently in the seventh decade. In histological classifications of the lesions, odontogenic benign lesions consisted of five ameloblastomas, three odontomas, and one cementoma. The non-odontogenic benign lesions were 30 fibrous hyperplasias, 20 hyperkeratoses (leukoplakia),16 hemangiomas and 11 papillomas. Non’odontogenic malignant lesions consisted of 42 squamous cell carcinomas, 3 malignant lymphomas and 2 malignant melanomas. Odontogenic cysts consisted of 31 radicular cysts, 20 primordial cysts and 13 dentigerous cysts. The non-odontogenic cysts consisted of 39 mucoceles, 25 post-operative maxillary cysts and 5 incisive canal cysts. In addition, 27 Sj6gren syndromes, 16 lichen planuses, 13 epulides and 46 chronic inflammatory granulation tissues were found.