Purpose: To assess the diagnostic accuracy of multi-detector CT angiography in the assessment of lower extremity arterial diseases by comparing the results with the standard of reference, conventional angiography. Patients and Methods: The studied group included 140 patients with suspected diagnosis of lower limb arterial disease on the basis of clinical examination or Doppler study with no age or sex predilection between March 2011 and November 2013. All patients were evaluated with lower limb angiography by multi-detector computed tomography and conventional angiography. The data obtained was statistically analysed to assess the accuracy of diagnosis of lower limb arterial diseases by MDCT angiography compared to conventional angiography that described in terms of count and percentage. Results: MDCT angiography findings showed 90.3% overall agreement with CA findings regarding the degree of stenosis while regarding the stenosis length MDCT angiography results showed 87.5% overall agreement with CA results. The overall sensitivity of MDCT angiography was 94.5%, specificity was 92.2%, and accuracy was 95.3%. Conclusion: Multi–detector row CT angiography can be used as an alternative to conventional angiography in the evaluation of aortoiliac and lower extremity arteries in patients with peripheral arterial disease.