Objective To compare the pathological characteristics of contrast-enhanced ultrasound (CEUS) and CT angiography (CTA) in elderly patients before endovascular aortic repair (EVAR) and their application value in the diagnosis of postoperative internal leakage. Methods A total of 83 patients undergoing EVAR in Ethnic Hospital of Guangxi Zhuang Autonomous Region were retrospectively enrolled between June 2021 and June 2023. Before and at 1 month after surgery, all underwent CTA and CEUS (interval <1 week). The diagnostic value of the two methods for preoperative aneurysm classifications, morphology, lesion sites, related parameters and postoperative internal leakage was compared. Taking CTA as the golden standard, the consistency of CEUS in the diagnosis of preoperative pathological types and postoperative internal leakage classifications was compared by Kappa analysis. Results There was no significant difference in tumor diameter, tumor length or diameter of abdominal aorta below kidney between CTA and CEUS (P>0.05). There was no significant difference in pathological classifications, morphology, lesions sites and other characteristics between CTA and CEUS (P>0.05). Compared with CTA, preoperative CEUS was of high consistency in the diagnosis of pathological types (Kappa=0.978). Taking CTA results as the golden standard, CEUS was of high consistency in the diagnosis of internal leakage types after EAVR (Kappa=0.855). There was no type VI or type V internal leakage detected by the two methods. Conclusion CEUS has comparable efficiency to CTA in preoperative evaluation of AAA’s pathological types and postoperative diagnosis of internal leakage classifications. CTA can be selected as a supplementary means for CTA according to patient"s indications, which is worthy of clinical promotion and application.