Objective To explore the level of CD62E+ endothelial microparticles in acute cerebral infarction patients and its relationship with vascular risk factors,degree of severity and prognosis.Methods Seventy patients with acute cerebral infarction and 70 non-cerebral infarction patients (controls),admitted to our hospital from January 2013 to September 2013,were selected in our study; U.S.national institutes of health stroke scale (NIHSS) was performed to evaluate the degree of severity; Barthel index (BI) was used to evaluate the prognosis; the levels of blood lipids,blood glucose,uric acid,fibrinogen (FIB),homocysteine (Hcy),C-reactive protein (CRP) and lipoprotein-associated phospholipase A2 (Lp-PLA2) were routinely measured; CD62E+ levels were detected by flow cytometry,and the relationships of CD62E+ level with vascular risk factors,degree of disease and prognosis were analyzed.Results The blood CD62E+ level of patients with acute cerebral infarction ([1.55 ±0.67]microparticle/μL) was significantly higher than that in the control group ([1.01 ±0.66] microparticle/μL,P＜0.05); CD62E+ level in patients with NIHSS scores＞5 ([2.03±0.61] microparticle/μL) was significantly higher than that in patients with NIHSS scores ≤ 5 ([1.25±0.37] microparticle/μL,P＜0.05).Spearman correlation analysis showed that CD62E+ level was significantly correlated with the stroke severity (NHISS scores,r=0.537,P=0.000) and lipoprotein-associated phospholipase A2 (Lp-PLA2) level (r=0.327,P=0.006),and negatively correlated with prognosis indicator (r=-0.634,P=0.000); other factors showed no significant correlation.Conclusion CD62E+ microparticle can reflect the severity and prognosis of acute brain infarction,and it may be an important biological marker for clinical application.Besides,the correlation between Lp-PLA2 and CD62E+ means that the level ofCD62E+ micro particles is associated with the stability of athemsclerotic plaques.