Ideal reconstruction of the oral cavity includes a durable lining that is thin, supple, and innervated, and that provides a lubricated surface that facilitates deglutition and speech. This paper describes the use of free colon transfer for relining the oral cavity. In three patients, segments of transverse colon, split along the antimesen-teric border, were transferred as free flaps on the middle colic vessels for large defects involving the alveolar ridge, buccal mucosa, floor of the mouth, tongue, and pharyngeal walls. All flaps were transferred successfully without adverse vascular events, abdominal complications, or oro-cutaneous fistulas. One flap was re-elevated 2 weeks postoperatively for additional mandibulectomy. Two patients received postoperative radiation therapy and another patient received planned preoperative radiotherapy.