Angiotensin II regulates blood pressure and contributes to endothelial dysfunction and the progression of atherosclerosis. Bone marrow-derived endothelial progenitor cells (EPCs) in peripheral blood contribute to postnatal vessel repair and neovascularization. Impaired EPC function in patients with hypertension and diabetes inhibits the endogenous repair of vascular lesions and leads to the progression of atherosclerosis. The number of EPCs in peripheral blood is inversely correlated with mortality and the occurrence of cardiovascular events. Angiotensin II-mediated signaling is implicated in oxidative stress, inflammation and insulin resistance, factors that cause EPC dysfunction. Blockade of the angiotensin II type 1 receptor may therefore present a new therapeutic target for enhancing EPC function.