For the last 10 years, about 300 cases of Skeletal class III or mandible prognathism received orthognathic surgery to correct jaw deformity and occlusion. This group of patients currently comprised above 50% of all surgical cases partly because the decrease of surgical cases of bimaxillary protrusion existed due to the advancement of extra-anchorage using skeletal screws for teeth or alveolar bone retraction. A standard procedure has been established for those cases who need setback of the mandible in Taipei-Veterans General Hospital including a comprehensive diagnosis from the beginning, goal of treatment, pre-surgical evaluation and management, bilateral sagittal splitting osteotomy, several clinical notes during surgery, and post-operative care. In this presentation, I would describe our experiences associated with the principle of surgical management, treatment sequence and a retrospectively analysis regarding to the stability and relapse after surgery for these cases.