Abstract： Objective The CT perfusion imaging of TIA and cerebral infarction (CI) resulting from TIA were compared to explore the possible influential factors for the process of TIA changing into infarction. Methods Patients clinically diagnosed ofTlA (TIA group) or CI from TIA (CI group) first took noncontrast CT scanning in a-cute phase. The positive planes were picked up according to the clinical symptoms and signs to perform CT perfusion (CTP) and CT angiography (CTA). The attack frequency, the duration of symptoms and risk factors of the two groups were summarized and statistically analyzed. Results The value of △rCBF in CI group was positively correla-ted with attack frequency. TIA group was significantly different from CI group in CTPI value, frequency and duration of attacks, and risk factors. Conclusions Progress of TIA changing into CI is closely related to the decreasing of △rCBF, attack frequency and duration and intracranial artery stenosis. For TIA patients with frequent or long-time attacks, CTP and CTA can get information of the cerebral blood flow and artery stenosis for prevention of ischemic stroke.