Since 1984, we have used the buccinator muscle mucosal flap for the treatment of mucosal defects after tumor resection, osteomyelitis of the mandible, closure of cleft palate fistulas, primary closure of very wide cleft palates, and lengthening of the soft palate. A study was made in the facial regions of 14 cadavers, and a comparison was made to descriptions found in the anatomic literature. It was confirmed in our dissections that the buccal artery, which reaches the posterior half of the muscle, is the major arterial pedicle of the buccinator and that it runs very close to the buccal nerve. Several veins originating from the lateral aspect of the muscle make the venous drainage of the buccinator even richer than its arterial supply. The abundant vascular supply from multiple interconnected pedicles supports the blood supply of the buccal mucosa. The motor innervation of the buccinator muscle comes from the facial nerve. The buccinator is considered to be a part of the sphincteric muscular system involving the functions of sucking, whistling, propelling food during mastication, and voiding the buccal cavity. The flap was utilized clinically in 38 patients: 24 to close primary cleft palates that required palate lengthening, 12 to close palatal fistulas, 1 to treat a mandibular osteitis, and 1 to repair the palate after tumor resection. We had three small fistulas as complications in our series owing to technical mistakes.