Objective By comparison and analysis of brain perfusion CT (CTPI) and angiography (CTA) for the diagnosis of acute ischemic stroke clinical value, which can provide a reference for clinical diagnosis of acute ischemic stroke patients and treatment. Methods Select the hospital 58 cases of acute ischemic stroke patients as this study, the use of CT in patients with head and neck CTPI, CTA examination. Statistics groups of diagnosis, and compared and analyzed. Results The inspection found, CT perfusion figure, which corresponds with the clinical symptoms of perfusion abnormalities at a total of 50 cases, the positive rate of 86.2% was significantly higher than that of CT examination in 16 cases, the positive rate of 27.6%, P<0.05. Perfusion abnormalities area CBV and CBF and MTT compare parameter values and clinical mirrored contralateral, P<0.05; by CTA examination revealed that the patient simply co-exist within the 10 carotid stenosis, 20 intracranial arterial stenosis alone, eight cases of internal carotid artery and intracranial arterial stenosis. CTA and CTPI joint inspection found offending vessels were using CTPI test positive in 38 cases, the positive rate of 65.5% was significantly higher than those without offending vessels were 12 cases, accounting for 20.7%, P <0.05. Conclusion The clinical application of CT brain perfusion and angiography may be better diagnosis of acute ischemic stroke, which is a clinical diagnosis, prevention and treatment provide important reference value.