The fibula is one of the most useful sources for harvest of a vascularized bone graft. The fibula is a straight, long, tubed bone, much stronger than any other available bone that can currently be used for a vascularized graft. It has a reliable peroneal vascular pedicle with a large diameter and moderate length. There is a definite nutrient artery that enters the medullary cavity, as well as multiple arcade vessels, which add to the supply of the bone through periosteal circulation. The vascularized fibula graft is used mainly for long segment defects of the long tubed bone of the upper and lower extremities. It can provide a long, straight length up to 25 cm in an adult. The fibula can be easily osteotomized and can be used in reconstruction of the curved mandible. Since the first description as a vascularized free fibula bone graft by Taylor in 1975 and as a mandibular reconstruction by Hidalgo in 1989, the fibula has continued to replace the bone and soft tissue reconstruction options in the field of maxillofacial reconstruction. For the better understanding of a fibular free flap, the constant anatomical findings must be learned and memorized by young doctors during the specialized training course for the Korean National Board of Oral and Maxillofacial Surgery. This article reviews the anatomical basis of a fibular free flap with Korean language.