A thyroglossal fistula is caused by a thyroglossal duct cyst. A thyroglossal cyst is a congenital cyst left in the neck as a result of incomplete degeneration of the thyroglossal duct during the development of the thyroid gland in early embryonic life, which does not completely disappear. The thyroglossal cyst does not have a significant impact on life. Once the thyroglossal fistula appears, the danger of thyroglossal fistula can also be manifested in the neck fistula, which repeatedly appears as mucus or purulent mucus, seriously affecting the patient’s quality of life and requiring surgical thyroglossal fistula removal treatment.