Based on diagnostic data in 35 patients with abdominal aortic aneurysm, which were obtained during ultrasonic scan echography, X-ray computed tomography and radioopaque angiography, and on their comparison with intraoperative findings, a diagnostic algorithm for examinations has been developed, which enables errors in the diagnosis to be excluded. The major diagnostic technique for abdominal aortic aneurysms has been found to be X-ray computed tomography which provided no errors in the assessment of the extent of aneurysms and the presence of their complicating components in all 35 patients. In high aneurysms of the abdominal aorta and suspected stenoses in the visceral, renal, and iliac arteries, X-ray computed tomography should be supplemented by radioopaque angiography to clarify the status of aortic branches.