Mandibular reconstruction with free flap has become a well-established technique. Effort are now focused on obtaining superior functional and aesthetic results. Improvements in the quality of the latter are possible with a systematic approach to shaping the bone graft. The fibular provides as much as a 25-cm segment of bone, more than enough to reconstruct any mandible defect. It has a consistent shape throufhout its length, a charecteristic that faciliates the contouring process. Owing to excellent segmental periosteal blood supply, the fibula can be osteotomized as many times as necessary to reproduce subtle nuances in mandible shape. This bone represents the ideal raw material for replacing a missing segment of mandible with great precision. Its superior tissue qualities and veratility make it well suited for most mandible defect. The authors experienced one case of retromolar trigone cancer excized surgically and reconstructed using fibluar osteoseptocutaneous flap, one staged. So, wo report it with the review of anatomy and surgical technique.