Objective To explore application value of 64-slice &128-strayum spiral CT angiography (CTA) in combination with color Doppler ultrasonography in the diagnosis of diabetic lower extremity vascular lesions. Methods One hundred and twenty eight patients with diabetic lower extremity vascular lesions admitted by the Hospital from February 2014 to April 2015 were retrospectively analyzed, 64 patients were subject to 64-slice & 128-strayum spiral CT and color Doppler ultrasonography and X-ray digital subtraction angiography (DSA) examination, DSA was treated as diagnostic criteria, and the diagnostic accuracy of 64-slice & 128-strayum spiral CT in combination with color Doppler ultrasonography in diagnosis of diabetic lower extremity vascular lesions were analyzed. Results CTA in combination with color Doppler ultrasonography determined 23 normal subjects, 48 patients with plaque, 42 patients with stenosis and and 15 patients with. DAS examination determined 23 normal subjects, 43 patients with plaque, 45 patients with stenosis, and 17 patients with occlusion. The difference between the therapy of CTA in combination with color Doppler ultrasonography on lower extremity vascular lesions and DSA was no statistically significant (P>0.05). Conclusion CTA can clearly show the orientation and inner diameter of the blood vessel, and color Doppler ultrasonography can monitor conditions of blood flow, and their combination can improve the diagnostic accuracy to large extent, providing reliable basis for clinical diagnosis.