Abstract： Objective To investigate the application of computer aided design-computer aided manufacture(CAD-CAM)technique in the reconstruction of mandible defect with individual titanium prosthesis. Methods Six patients with large mandibular ramus and angle tumor were spiral CT scanned preoperatively, and the CAD-CAM was used to design and make individual titanium prosthesis for reconstructing the mandibular defects after resection of the tumor. The prosthesis were assembled during operation. Postoperative follow-up period was 9-38 months.Results The design and manufacture of titanium prosthesis by use of CAD-CAM technique was convenient and the prosthesis fitted the defects very well.The outline of the face,the occlusion and function were restored. After 9-38 months of follow-up, the mandibular symmetry was good.Conclusions The application of CAD-CAM provided accurate simulation and fast manufacturing process for the titanium prosthesis in the repair of mandibular defect.