Eustachian tube is a complex and hidden structure,which consists of three parts:bone,cartilage and the bone-cartilage junction. The eustachian tube is very important for maintaining the middle ear healthy and normal hearing.The abnormal function of the eustachian tube 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. However, at present, it is not well mastered for the anatomical structure and physiological function of the eustachian tube.This paper summarizes and expounds the related research on the anatomical structure of the eustachian tube. The purpose of this paper is to provide reference for clinical prevention and treatment of related diseases.