A fatal case of ameloblastoma which was treated for over thirty-five years is reported. The treatment included various surgical procedures and X-ray treatment. Clinically the tumour was very malignant with a highly infiltrative character. It infiltrated into the soft tissues of the face, neck, and finally into the skull. No lymphatic spread was noticed. Histologically the tumour was a typical ameloblastoma of follicular pattern without malignant transformation.