Objective To investigate the correlation between C-reactive protein (CRP) level at admission and severity and early outcome of acute ischemic stroke.Methods Inpatients with acute ischemic stroke were enrolled retrospectively.The demographic and clinical data were collected.The National Institutes of Health Stroke Scale (NIHSS) at admission was used to evaluate the neurologic deficits,≤8 was defined as a mild stroke and ＞ 8 was defined as a severe stroke.The modified Rankin scale was used to evaluate the outcomes at discharge,0-2 was defined as good outcome and ＞ 2 was defined as poor outcome.Multivariate logistic regression analysis was used to determine the independent influencing factors of severity and early outcome of acute ischemic stroke.Results A total of 120 patients with acute ischemic stroke were enrolled in the study.Their mean age was 63.35 ± 11.51 years,71 (59.17％) were males;81 had mild stroke (67.5％),39 (32.5％) had moderate to severe stroke;71 (59.17％) had good outcome,and 49 (40.83％) had poor outcome.There were significant differences in the age,CRP level,and proportions of ischemic heart disease,atrial fibrillation,smoking,and drinking between the mild stroke group and the moderate to severe stroke group (all P ＜0.05).Multivariate logistic regression analysis showed that ischemic heart disease (odds ratio [OR] 4.407,95％ confidence interval [CI] 1.100-17.653;P=0.036),atrial fibrillation (OR 6.603,95％ CI 1.190-36.635;P =0.031) and CRP (OR 1.022,95％ CI 1.001-1.043;P =0.041)were independently and positively correlated with the severity of stroke.There were significant differences in baseline NIHSS score,fibrinogen and CRP level,as well as the proportions of the patients with atrial fibrillation,smoking,and drinking between the good outcome group and the poor outcome group (all P ＜0.05).Multivariate logistic regression analysis showed that smoking (OR 8.895,95％ CI 1.699-46.557;P=0.010),baseline NIHSS score (OR 2.241,95％ CI 1.567-3.206;P ＜0.001),and CRP (OR 1.195,95％ CI 1.030-1.386;P =0.019) were independently correlated with the early poor outcomes.Conclusion CRP level at admission was the independent influencing factor of severity and early outcome of acute ischemic stroke.