en Otorhinolaryngology Otorhinolaryngology case report case report Thyroglossal duct cyst is a well-known congenital entity, and its embryonic development and clinical presentation are well understood. Very little can be added to the classic material found in the world literature. Rare cases of unusual clinical presentation have also been reported. Our case of endolaryngeal thyroglossal duct cyst is reported because of its unique endolaryngeal presentation, having no characteristic external cystic mass. This case is reported along with its cr and FVL studies and pathological slides. 251 254 http://mjiri.iums.ac.ir/browse.php?a_code=A-10-1-361&slc_lang=en&sid=1 N MOKHTARI 20031947532846005109 20031947532846005109 Yes From the Department of Otolaryngology, Head and Neck Surgery, Mashhad University of Medical Sciences, Mashhad A TABATABAI 20031947532846005110 20031947532846005110 No the Department of Pathology, Ghaem Hospital, Mashhad R ABDI 20031947532846005111 20031947532846005111 No the Department of Radiology, Mazandaran University of Medical Sciences, Sari, Islamic Republic of Iran.