Abstract： Mandibular defect is one of the common defects of maxillofacial region, which can seriously affect the appearance, chew and speech. The ultimate goal of functional reconstruction of mandibular defect is to restore mandibular appearance, denture and occlusal function. Vascularized bone grafting is an effective method for reconstruction of mandibular defect, especially in treatment of large defect. However, functional reconstruction of mandibular defects involves multiple specialties, many technical details and long treatment cycle, resulting in a small proportion of functional reconstruction. To establish standard operating procedures, Society of Oral Maxillofacial Rehabilitation, Chinese Stomatological Association has organized a lot of experts to establish expert consensus statement on reconstruction principle for mandibular defect, referred to standard procedure of indication, preoperative evaluation, choice of donor site, digital technology aided surgery, recommendations of the operation in the process of residual mandibular position fixed, the mandibular body molding denture and common post?operative complications, in order to promote the reconstruction of mandibular defect treatment and improve the quality of reconstruction.