Objective To evaluate the diagnostic value of lower extremity arterial angiography (CTA) in lower extremity arterial occlusive lesions (ASO). Methods A total of 108 suspected lower extremity ASO patients admitted to our hospital from January 2020 to June 2021 were selected and divided into two groups according to the random number table method: Group A and group B, 54 cases in each group. All patients underwent lower extremity CTA examination by 256slice CT. Group B: The coefficient 20 mL, the total velocity is 4) 5 mL/s. The second phase contrast medium was 30 mL, the flow rate was 45 mL/s. In the third phase, the contrast medium was 70 mL, and the flow rate was 3 mL/s. The fourth phase was 20 mL saline, with a flow rate of 3) 0 mL/s. Four consecutive injections without interruption). The obtained images were uploaded to the workstation for 3D reconstruction, and the image quality of the two groups of CTA was compared. The results of digital subtraction angiography (DSA) were used as the gold standard to compare the diagnostic effect of ASO between the two groups. Results CTA group B image of calf, foot artery areas of segmental arteries imaging defective rate is lower than group A (000% 185%vs1481%,vs1481%), vein enhancement rate 185% lower than A set of 1481% (P<005). Group B CTA images leg, foot area of the artery artery branches, vascular imaging score were higher than in group A (P<005). Reference DSA results, group B CTA images of lower limb vascular stenosis degree grading diagnosis coincidence rate 9444% (51/54) higher than that of group A, 8148% (44/54), the difference was statistically significant (P<005). Sensitivity and accuracy of the diagnosis of ASO B group were higher than in group A (9773%vs8222%, 9630%vs8333%), the difference was statistically significant (P<005). Conclusion The new selfdesigned injection scanning scheme can improve the imaging effect of lower extremity CTA, reduce the interference of poor imaging and venous imaging, improve the image quality of lower extremity CTA and the diagnostic efficiency of ASO, which has the value of clinical application.