Objective To explore the evaluated value of CTP images and dynamic angiography (4D-CTA) images obtained by whole brain CT perfusion imaging (WBCTP) in the diagnosis of cerebrovascular stenosis or occlusion. Methods A total of 45 cases of patients who were highly suspected as ischemic cerebrovascular disease (ICVD) in department of neurosurgery of our hospital were given head WBCTP and DSA examination. The CTP perfusion parameters [mean transit time (MTT), cerebral blood flow (CBF), cerebral blood volume (CBV)] and cerebrovascular stenosis or occlusion in 4D-CTA images were observed, and DSA was taken as a reference to analyze the diagnostic value of CTP and 4D-CTA in cerebrovascular stenosis or occlusion in ICVD. Results DSA examination showed that 42 cases were diagnosed as positive ischemic cerebrovascular disease and 3 cases were negative ischemic cerebrovascular disease among 45 cases of patients, and a total of 410 head and neck arteries were examined and 101 cerebral arteries were found with stenosis or occlusion. CTP perfusion images showed that the MTT value of brain tissue of affected side was significantly larger than that of healthy side (P<0.05), and the CBF and CBV values were significantly smaller than those of healthy side (P<0.05). 4D-CTA images showed the detection rate of cerebrovascular stenosis or occlusion in patients with abnormal brain CTP perfusion was significantly greater than that of patients with normal brain CTP perfusion (P<0.05). Taken DSA results as references, the sensitivity, accuracy and specificity of CTP images combined with 4D-CTA images obtained by WBCTP were 89.11% (90/101), 97.09% (300/309) and 95.12% (390/410) respectively in judging cerebrovascular stenosis or occlusion. Conclusion CTP combined with 4D-CTA can accurately diagnose the degree of cerebrovascular stenosis and occlusion, and help to develop a reasonable treatment regimen and improve the treatment effects of cerebrovascular disease.