Purpose: The purpose of this study was to develop and assess the potential feasibility of reconstructing composite defects of the mandible with a local pedicled osteomyocutaneous mandibular flap. Materials and Methods: The flap design was established based on anatomic principles. A prospective evaluation of the flap was then performed in a fresh cadaver model, and, subsequently, its vascular integrity was documented with angiography. Results: The pedicled osteomyocutaneous mandibular flap was technically simple to raise and had an exceptionally long arc of rotation, which should enable it to fill most compound segmental defects of the mandible. Angiographic studies of the harvested flaps done under fluoroscopic guidance confirmed that excellent vascularity of all components of the flap was present. Conclusions: The pedicled osteomyocutaneous mandibular flap appears to have a sound anatomic basis. Clinical evaluation is needed to fully elucidate its potential role in head and neck reconstruction.