Objective To investigate the relationship between neutrophil lymphocyte ratio（ NLR） and intracranial and extracranial atherosclerosis stenosis in patients with cerebral infarction. Methods A total of 202 patients with acute ischemic stroke who were hospitalized in the Neurology Department of Shengjing Hospital of China Medical University from June 2016 to June 2017 were selected as cerebral infarction group. According to the subtype classification criteria of the Trial of Org 10 172 in Acute Stroke Treatment（ TOAST）， the cerebral infarction group was divided into large artery atherosclerotic（ LAA） cerebral infarction group and non-LAA group. Meanwhile 109 patients without cerebral arteriosclerosis and cerebral infarction were selected as the control group. 32 patients in the atherosclerotic cerebral infarction group were followed up. The NLR values were reviewed in outpatient clinic from 1 to 6 months after onset， and the NLR level in acute and recovery phase was compared. According to head MRA and carotid ultrasound， the patients were divided into simple intracranial atherosclerotic stenosis group， simple extracranial atherosclerotic stenosis group， intracranial and extracranial atherosclerotic stenosis group， non-stenosis group. The general clinical characteristics of the groups were compared， and the variables（ P＜0.05） were included in multivariate Logistic regression analysis. The cerebral infarction group was divided into different subgroups according to the location and degree of atherosclerosis， and the NLR level was compared. Results The NLR level of cerebral infarction group was significantly higher than that in the control group（ P＜0.05）. There was no significant difference in the NLR level between the recovery period and the acute phase of cerebral infarction in the follow-up patients（ P＞0.05）. Multivariate Logistic regression analysis of intracranial atherosclerotic stenosis showed that NLR was significantly associated with intracranial atherosclerosis after adjusting for other risk factors（ OR=2.393， 95%CI=1.389-4.123，P＜0.05）. There was no significant difference in NLR between two groups with different atherosclerotic stenosis sites and degrees（ P＞ 0.05）. Conclusions The level of NLR is associated with cerebral infarction， but not related to acute cerebral infarction. NLR is the risk factor of cerebral atherosclerosis and may be an independent predictor of intracranial atherosclerotic stenosis. There is no correlation between NLR and the position and extent of atherosclerosis.