〔Abstract〕 Objective To observe the role of the renin-angiotensin system in myocardial injury induced by experimental vascular dementia. Methods Eighteen adult male rats were categorized into a normal group, sham group, and modified 2-vessel occlusion group(model).To assess the myocardial injury caused by experimental vascular dementia, immunostaining was conducted to evaluate the interstitial collagen fraction and myocyte cross-sectional area.The concentrations of angiotensin Ⅱ(Ang Ⅱ) and angiotensin 1-7(Ang1-7) in the serum, as well as the expression levels of angiotensin converting enzyme(ACE),angiotensin converting enzyme 2(ACE2),Ang Ⅱ,Ang1-7,angiotensin type 1(AT1) receptor, and Mas receptor in the myocardium, were assessed. Results Modified 2-vessel occlusion led to pronounced cognitive dysfunction(P<0.01) and myocardial injury(P<0.000 1) when compared to the sham and normal groups.Additionally, modified 2-vessel occlusion induced significant upregulation of the ACE/Ang Ⅱ/AT1 receptor axis(P<0.01) and downregulation of the ACE2/Ang1-7/Mas axis(P<0.05) of the renin-angiotensin system in the myocardium. Conclusion Myocardial injury in rats with experimental vascular dementia may be related to dysregulation of the renin-angiotensin system.