Ameloblastoma, a benign tumor of odontogenic type, represents 10% of all tumors of the jaw. It is localized in the mandible(80%) and in the maxilla(20%). In every case, the selection of the surgical treatment must consider some fundamental elements, including the age and general state of health the clinicopathological variant, and the localization and extent of the tumor. This study was invested the clinicopathological findings of 23 patients with ameloblastoma which had been diagnosed by biopsy during the period of 1987 to 2005 at Chonnam National University Hospital. And it contained the statistical analysis according to the treatment methods and the clinicopathological findings such as sex, age, location, chief complaints, duration, radiographic findings, histologic findings, treatment methods. The results obtained are were follows. The age of patient ranged from 10 to 91 years(means, 35.9 years) at biopsy. Thirteen(57%) of the 23 subjects were males, and 10(43%) were females. Twenty(87%) of the 23 ameloblastomas were located in the mandible. Swelling was the most common symptom and was experienced by 20(87%) patients. Radiographically, 11(48%) of the 23 tumors were unilocular with a well-demarcated border and 12(52%) were multilocular. The most common histologic pattern was plexiform and acanthomatous rather then follicular. Conservative treatment was performed 7 cases(30%), radical treatment 11 cases(48%), and combined treatment 5 cases(22%). Follow-up period ranged from 2.1 years to 22 years(mean 5.1 years). Based on the above results, surgical excision after marsupialization was found to be useful as a preliminary treatment of the large cystic ameloblastoma in children and adolescents. On the contrary, the lesion with a soap bubble appearance, the one with ineffective marsupialization was subjected to extensive excision of the tumor with a wide margin of normal bone.