Objective: To explore the application value of high frequency ultrasound and intraoperative contrast-enhanced ultrasound (CEUS) in the treatment of pediatric suppurative appendicitis with fecaliths by endoscopic retrograde appendicitis therapy (ERAT) combined with digital cholangioscopy. Methods: Retrospective analysis of 48 children with suppurative appendicitis and fecaliths formation admitted to our hospital from September 2022 to November 2023. All patients were accurately evaluated using high-frequency ultrasound before treatment. During the treatment process, combined with intraoperative contrast-enhanced ultrasound imaging, the successful fecaliths removal and the presence or absence of perforation in the appendix were observation and recorded. According to the endoscopic treatment results, the patients were divided into two groups: the successful fecaliths removal group and the intraoperative perforation group, the consistency between the ultrasound and endoscopic findings during the treatment process was analyzed. After treatment, both groups of children underwent regular ultrasound examinations and recorded corresponding indicators. The time for each observation indicator to return to normal reference values, the time for accompanying symptoms to disappear, and the time for laboratory tests to return to normal were compared. Analyze the excellent and good cure rates, complications, etc. of the two groups of children.Results: In this study,there were 39 successful fecaliths removal cases and 9 intraoperative perforation cases. There were significant statistical differences in ultrasound observation of the thickness of the appendix wall and omentum, fever, abdominal pain symptoms, WBC count, and recovery time of CRP between the two groups after treatment; There were no significant complications in the successful fecaliths removal group, and one patient in the intraoperative perforation group developed a periappendiceal encapsulated abscess. However, the cure and excellent rates of the two groups were 100.00% and 88.89%, respectively, with no statistical difference between the two groups (P>0.05).Conclusion: High frequency ultrasound and intraoperative contrast-enhanced ultrasound guided ERAT combined with the digital cholangioscopy for the treatment of pediatric suppurative appendicitis with fecaliths are real-time and accurate, with a high cure rate and fewer complications. They can be an effective conservative treatment method for this disease and are worth promoting and applying.