Aim To observe expression of urotensin-Ⅱ(U-Ⅱ) on vascular epithelium in smoked rat brain,and to discuss the mechanism of ischemia in brain caused by smoking. Methods 60 health Wistar rats were divided into 6 groups: normal group,short-time and big-dose smoking group,long-time and big-dose smoking group,long-time and small-dose smoking group,giving-up smoking group,control group.We obtained brain following experiment ending and observed expression of U-Ⅱ in smoked rat by immunohistochemistry stain. Results The expression of U-Ⅱ in normal group and control group was weak.The significant different expression was observed in other groups(P><0.05).Giving up smoking can reduce the expression of U-Ⅱ. Conclusion Smoking can make more U-Ⅱ expression in endothelial cell.There is prominent dose-dependent and time-dependent relationship between smoking and expression of U-Ⅱ.Giving up smoking can reduce expression of U-Ⅱ.The increase of U-Ⅱ plays an important role in ischemic cerebral vascular disease(ICVD) caused by smoking.