Objective: To investigate the applied value of platysma myocutaneous flap in the reconstruction of tissue defects of the floor of the mouth.Methods: A total of nine patients with floor of the mouth carcinoma underwent immediate reconstruction of intraoral defects using platysma myocutaneous flaps.A supraomohyoid neck dissection was performed in six patients with squamous cancer.One patient received rectangular resection of the mandibular bone.Five patients received assistant radiotherapy post-operation.