The authors report the very rare case of a congenital immature teratoma arising from the nasopharyx in a full term female neonate. The tumor also extended to the oral cavity, particularly the right tonsillar fossa without intracranial involvement leading to upper airway obstruction and secondary Escherichia coli
pneumonia. The immature part of the tumor in the head and neck region is not a poor prognostic indicator and chemotherapy is useless. In the presented case, the mass was widely excised without postoperative complications. To the best of our knowledge, this is the first reported case in Thailand.

Keywords: Nasopharynx, Immature teratoma, Congenital