Objective To investigate the correlation between vertebrobasilar artery stenosis and serum biochemical indexes in patients with posterior circulation cerebral infarction（PCCI）．Methods One hundred patients with PCCI admitted to our hospital were selected as the study objects,and the clinical data of all patients were retrospectively analyzed．The patients were divided into unstable plaque group（n=35）,stable plaque group（n=36）and no plaque group（n=29）according to the degree of vertebrobasilar artery stenosis．The general clinical conditions,serum levels of neurocytokines and inflammatory factors of the patients were compared,the correlation between vertebrobasilar artery stenosis and serum biochemical indicators in patients with PCCI was analyzed．Results The recurrence and NIHSS score of the 3 groups were significantly different,the unstable plaque group was significantly higher than the other 2 groups（P<0.05）,but there was no significant difference between the stable plaque group and the no plaque group（P>0.05）．The levels of brain-derived neurotrophic factor（BDNF）,neuron-specific enolase（NSE）and central nerve specific protein（S100β）in the three groups were significantly different．BDNF in unstable plaque group was lower than that in stable plaque group and no plaque group,while NSE and S100β in unstable plaque group were higher than that in stable plaque group and no plaque group（P<0.05）．There was no significant difference between stable plaque group and no plaque group（P>0.05）．The levels of serum C-reactive protein（CRP）,interleukin-37（IL-37）,tumor necrosis factor-α（TNF-α）,vascular cell adhesion molecule-1（VCAM-1）,intercellular adhesion molecule-1（ICAM-1）and human cartilage glycoprotein 40（YKL-40）in 3 groups were significantly different．The unstable plaque group was higher than the other two groups（P<0.05）,but there was no significant difference between the stable plaque group and the no plaque group（P>0.05）．Pearson Line correlation analysis showed that vertebrobasilar artery stenosis was negatively correlated with BDNF,and positively correlated with NSE,S100β,CRP,IL-37,TNF-α,VCAM-1,ICAM-1,YKL-40（P<0.05）．Multivariate Logistic regression analysis showed that BDNF,NSE,ICAM-1 and YKL-40 were independent risk factors for vertebrobasilar artery stenosis（P<0.05）．Conclusions The more severe degree of vertebrobasilar artery stenosis in patients with PCCI,the higher recurrence rate and more serious the impact on the neurological function of patients．At the same time,the levels of serum related neurocytokines and inflammatory factors were significantly related to the severity of vertebrobasilar artery stenosis．BDNF,NSE,ICAM-1 and YKL-40 can be used as important indicators to predict the severity of vertebrobasilar artery stenosis in patients with PCCI．Therefore,monitoring the patient’s serum biochemical indicators of angiography can provide reference for clinical diagnosis and prognosis judgment．