Objective To study the application value of CT perfusion imaging (CTP) in seizure intervals of patients with transient ischemic attack (TIA). Methods 52 patients with TIA in our hospital were selected as the study objects. All of them underwent CTP. The changes of perfusion parameters in patients with anterior and posterior circulation TIA were observed, including the time to peak (TTP), regional cerebral blood flow (rCBF), regional cerebral blood volume (rCBV) and mean transit time (MTT). The value of CT perfusion imaging in diagnosis of cerebral blood flow in patients with TIA was quantitatively analyzed. Results Of the 21 patients with anterior circulation, the rate of abnormal perfusion was 85.71%. RTTP and rMTT in abnormal perfusion region of patients with anterior circulation TIA [(15.11±1.74)s、(41.13±2.58)s] was significantly higher than that in the fellow normal region (P<0.05) while rCBF (54.16±7.15) ml/100g·min was significantly lower than that of fellow normal region (P<0.05). There was no significant difference in rCBV between the two groups (P>0.05); In 31 patients with posterior circulation TIA, the rate of abnormal perfusion was 64.52%. RTTP and rMTT in abnormal perfusion region in patients with posterior circulation TIA [(13.25±1.25), (16.16±3.49)] was significantly higher than that in the fellow normal region (P<0.05) while rCBF（50.34±2.44）ml/100g·min was significantly lower than that in fellow normal region (P<0.05). There was no significant difference in rCBV between the groups (P>0.05). Conclusion CT perfusion imaging can observe the cerebral blood flow in patients with TIA, and detect abnormal cerebral perfusion in seizure intervals of the attacks in time. It can be used in the observation and diagnosis of changes of haemodynamics in patients with early lesions.