Abstract: OBJECTIVE To study the effect of Tangkeming (TKM) on blood-retinal barrier (BRB) in diabetic rats. METHODS Diabetic retinopathy rats were induced by STZ. The blood biochemical indexes were detected. Retinal vascular permeability was measured by Evans blue. The expression of occludin and VEGF in retina of diabetic rats were determined by qPCR and immunohistochemistry， respectively. RESULTS Administration of TKM to diabetic retinopathy rats significantly ameliorated the levels of GLU， TG and TC in serum. The Evans blue contents in dry retina tissue remarkedly reduced upon TKM treatment. The level of occludin mRNA was up-regulated and the expression of VEGF in retina was down-regulated by TKM in diabetic rats. CONCLUSION TKM protects the BRB by inhibiting expression of VEGF associated with occludin.