We reviewed 56 patients who received mandibulotomy at Yonsei medical center between 1989 and 1999. We also analysed the complications associated with mandibulotomy and its contributing factors. The complications occur in 16 patients(28.6%) and are classified into two categories; intraoperative and postperative complications. Nonunion was observed in 5 patients and osteoradionecrosis in 5. The patients who received preoperative radiation therapy were more tend to develop nonunion and osteoradionecrosis. This study suggests the benefits of mandibulotomy as a surgical approach to oral cancer: 1. Paramedian osteotomy was recommended for preservation of neurovascular bundle and ease of surgical access. 2. By using thin saw blade, reapproximation was improved with minimal bone loss. 3. osteotomy on anterior mandible which lies outside the usual portals of radiation therapy decreases the incidence of osteoradionecrosis.