Diabetic retinopathy(DR)is a serious complication of diabetes mellitus(DM)and an important cause of vision loss in DM patients,macular edema and neovascularization are the two main reasons for it.Vascular endothelial growth factor inhibitor is one of most popular treatment methods for this disease,intravitreous injection of avastin for DR has received more and more attention in recent years,and it provides another treatment method to ensure visual acuity for DM patients.