Objective <p>To explore and compare the diagnostic value of color Doppler ultrasound and CT for abdominal aortic dissection aneurysm.</p> Methods <p>A retrospective analysis was conducted on the data of 104 patients with suspected abdominal aortic dissection aneurysm treated in our hospital from May 2018 to May 2020. Using symptoms, signs, and aortography results as the diagnostic gold standard, we analyzed the diagnostic agreement rates of color Doppler ultrasound and CT, and compared the diagnostic efficacy of the two methods (sensitivity, specificity, positive predictive value, negative predictive value).</p> Results <p>The diagnostic agreement rate of color Doppler ultrasound was higher than that of CT, and the number of aortic rupture sites, the number of affected branch vessels, the formation of intramural thrombus, and arterial wall calcification were also higher than those found by CT, with statistically significant differences (<i>P</i> &lt; 0.05). Additionally, the sensitivity, specificity, positive predictive value, and negative predictive value of color Doppler ultrasound were higher than those of CT, with statistically significant differences (<i>P</i> &lt; 0.05). Finally, the incidence of adverse reactions in the color Doppler ultrasound group was lower than that in the CT group (<i>P</i> = 0.031).</p> Conclusion <p>Color Doppler ultrasound is more effective in the clinical diagnosis of patients with abdominal aortic dissection aneurysm, which is beneficial for improving disease detection rates, and is superior to CT with lower adverse reactions. It is worthy of clinical recommendation.</p>