Diabetic retinopathy(DR) is a microvascular complication of diabetes,and the main reason for adult blindness in developed countries.Along with social progress and people’s living standards improving,the incidence of diabetes is increasing.And it has become a hazard to human health,a serious violation of multiple body systems and metabolic diseases.The ocular complications caused by it has become one of the world’s major blinding eye diseases.Therefore,the study of DR in the pathogenesis and its therapeutic approach is currently an important issue in the field of ophthalmology research.The latest research shows that eye tissues are with independent synthetic renin-angiotensin system(RAS) capabilities,but also RAS participates in the occurrence and development of DR,so preventing and blocking the RAS may have important therapeutic value of DR.