Objective:To assess the diagnostic accuracy of 16-slice computed tomographic angiography (CTA) in detecting intracranial aneurysms compared with digital subtraction angiography(DSA) and surgical findings. Methods:356 cases with suspected intracranial aneurysms received CT scan,and the results were compared to DSA and intraoperative findings retrospectively. Results:Combining CTA,DSA and intraoperative findings,215 aneurysms were detected in 195 of the 356 patients. Five aneurysms were missed when using CTA. Nine aneurysms detected by CTA were not clearly displayed at DSA,five were proved at surgery and four were not performed by surgical treatment. There was no significant difference in sensitivity between 16-slice CTA and DSA. Conclusion:16-slice CTA has a very high sensitivity,specificity,and accuracy of detecting aneurysms,and it is sensitive enough to replace conventional DSA in the triage,diagnosis,and treatment planning in patients with intracranial aneurysms.