Abstract： Objective To investigate the diagnostic value of aortocranial DSA in collateral circulation in elderly patients with serious stenosis or occlusion of the internal carotid artery. Methods Twenty-three elderly patients with serious stenosis or occlusion of the internal carotid artery, admitted to our hospital from August 2008 to July 2010, were chosen; their DSA findings and prognoses were retrospectively analyzed. Results Of these 23 patients, the collateral circulation was seen in 18(78.3%), including compensations from anterior communicating artery (n=16), posterior communicating artery (n=6), anterior together with posterior communicating artery (n=3), anterior choroidal artery (n=5),meningina artery between anterior cerebral artery and posterior cerebral artery (n=5), meningina artery between posterior cerebral artery and middle cerebral artery (n=4), ophthalmic artery (n=15), blood vessel between posterior cerebral artery and superior cerebellar artery (n=3), and blood vessel among superior cerebellar artery, anterior inferior cerebellar artery and posterior inferior cerebellar artery (n=2); after conservative treatment and long time follow-up (1 to 22 months with a mean of 11.2 moths),disappearance of clinical symptoms and no recurrence were found in these 18 patients. Five patients were noted without compensatory collateral circulation: the 2 paralysis patients could not take care of themselves even with the improvement of myodynamia from grade 0 to grade Ⅲ; the 2 patients with disturbance of consciousness showed no recovery and died from lung infection; the left 1 patient was having aphasia. Conclusion DSA can accurately define ways and compensative ability of collateral circulation in elderly patients with serious stenosis or occlusion of the internal carotidartery, which can put forward reliable evidences for their treatments and prognoses.