This report based on 300 cases of serious diseases in maxillofacial region by radiograms seen at the department of dental radiodontics, infirmary school of dentistry, Kyung Hee University from October 1971 to August 1974. The maxillofacial diseases were analysed upon the following items, such as 1) the frequency of dominant diseases, 2) sex-ratio of male to female, 3) predominant region of diseases, 4) comparison with the age, 5) the incidence of diseases in relative to the individual teeth. The results were obtained as follows. 1) Among the total of 300 cases of the patients, the frequency of dominant diseases of patients were fractures of facial bone (44.3±2.87%), inflammatory diseases (22.7±2.39%), cysts (11.1±1.62%), tumors (10.7±1.77%), maxillary sinusitis (7.9±1.56%), temporomandibular joint disorders(3.3±1.05%) in the order. 2) The ex-ratio of male to female in occurence of jaw fractures were 7.3:1, temporomandibular joint disorders were 2.1:1, inflammatory diseases were 1.8:1, maxillary sinusitis were 1.7:1, but tumors were equal to 1:1, while cysts were 1:1.2 in sex difference. 3) The predominant region of mandibular fractures were symphysis(17.3±3.27%), canine region (15.0±3.09%), and angle region (14.3:±3.04%) in the order. Inflammatory diseases were occured frequently in mandible and it's left side were a little dominant. Odontogenic cysts were observed frequently in maxilla, but regardless of right and left. Carcinomas were involved most frequently in maxilla, while sarcomas and ameloblastomas in mandible. Frequency of the maxillary sinusitis were dominant right side and molar area, also temporomandibular joint disorders were right side. 4) To study comparison with the age jaw fractures showed the highest ratio at the 2nd decade(32.3±4.06%), and 3rd decade (27.8±3.89%), 4th decade (19.6±3.44%), 6th decade (9.0±2.47%), 5th decade(6.0±2.06%), 1st decade (5.3±1.95%) in the order. But 7th decade were not involved entirely. Frequency of the inflammatory diseases were the highest in the age group of 3rd decade (28.0±5.44%), and those of cysts were 5th decade (24.2±7.22%), temporomandibular joint disorders were 3rd decade (60.0±15.49%). Tumors were occured frequently over the 4th decade especially malignint tumors over the 5th decade, but maxillary sinusitis were rearless of age except for 2nd decade. 5) About the incidence of diseases in relative to individual teeth, fractures of facial bone were most frequently involved the maxillary and mandibular anterior teeth, and mandibular 3rd molar region. Cysts were maxillary anterior region inflammatory diseases were mandibular molar region maxillary sinusitis were maxillary 1st molar, region but tumors were regardless of individual teeth.