Abstract: The incidence of lowgrade appendix mucinous neoplasms (LAMN) is low, and it is often manifested as appendicitis and abdominal mass. Due to the lack of specific clinical features, preoperative diagnosis is difficult. With the  popularization of colonoscopy and application of endoscopic ultrasound (EUS) in the colon, the detection rate of LAMN is rising.At the same time, more doubts and problems need further exploration and solution. For example, the features of LAMN in EUS, the advantages of EUS compared with other imaging examinations, its differential diagnosis of other appendic diseases, the significance and accuracy of preoperative staging. More research and summary need to select which kind of ultrasound endoscope (Linerarray echoendoscope, radialarray echoendoscope and miniprobe)    more suitable for detecting appendix diseases.

Key words: endoscopic ultrasonography； appendiceal neoplasms, myxoma; , preoperative staging