Resection of primary tumors of the floor of the mouth mandates consideration of the management of the mandible which may be either involved by direct invasion or by close proximity. Segmental mandibulectomy can usually be performed when the tumor is either massive or directly invading the mandible. However, the cosmetic and functional results of segmental mandibulectomy are unsatisfactory. Whenever the tumor is close to the mandible or adherent to the periosteum, consideration should be given to marginal mandibulectomy. Over a period of 8 years, we have treated 65 patients with carcinoma of the floor of the mouth. Of these, 22 underwent marginal mandibulectomy. The number of patients staged T1, T2, and T3 were 4, 13, and 5 , respectively. Most had oblique marginal mandibulectomy including the resection of the upper rim and medial cortex of the mandible. Vertical or horizontal mandibulectomy was rarely used. In each patient the preoperative workup included dental X-rays, panoramic films, and computerized tomography (CT) scan of the head and neck. The decision as to the extent of mandibulectomy was made primarily based on the clinical judgement. Seven patients underwent marginal mandibulectomy through the open mouth. However, in the remaining 15 patients, the cheek flap approach was utilized. The defect following marginal mandibulectomy was reconstructed either with split thickness skin graft, tongue flap, or myocutaneous flap. Small defects were left open to heal by granulation and secondary intention. Split thickness skin grafts healed very well over the surface of resected mandibles. Good local tumor control was achieved at the primary site and the functional and cosmetic results were excellent.