Eustachian tube is a complex and hidden structure,which consists of three parts:bone,cartilage and the connection between bone and cartilage.it is necessary to keep the middle ear healthy and normal hearing.abnormal eustachian tube function can lead to ear swelling,tinnitus,secretory otitis media and tympanic membrane invagination,which is a common cause of middle ear diseases in adults and children.with the rapid development of surgical techniques such as nasal endoscope and otoscope,the anatomical structure of the eustachian tube has attracted much attention,but at present,the anatomical structure and physiological function of the eustachian tube are not well mastered.this paper aims to summarize and expound the related research on the anatomical structure of the eustachian tube,and provide reference for clinical prevention and treatment of related diseases.