Distraction osteogenesis (DO) is a tissue engineering method to regenerate new bone. The application of DO in the field of oral and craniomaxillofacial surgery has provided a promising alternative as it can be integrated with conventional surgical technique for bone lengthening or expansion. This technique has the advantages of providing superior amount of bone lengthening thus eliminating the need of autogenous graft and donor site morbidity, can be applied in young patients and allows simultaneous expansion of the surrounding soft tissues. In this chapter, we provide a comprehensive overview of the background history and development of DO which is based on Ilizarov technique, along with its basic principles, indications, classification of DO devices and protocol in craniomaxillofacial bone lengthening or expansion. Its clinical applications which include alveolar DO, mandible DO, maxilla DO, transport DO and craniofacial DO are clarified. This technique however requires proper understanding of clinical and technical components to avoid potential complications which include relapse, infection, adjacent structure injury, device failure and other complications. The emerging results of research and advances in DO are further elaborated at the end of this chapter.