To observe the effect of Huoxue Jiedu Recipe (HJR) on the morphology of retinal blood vessels of diabetic rats, and to explore its underlying mechanism.Methods:Streptozotocin(STZ, 65 mg/kg) was intraperitoneally injected to rats to induce diabetes. The diabetic rats were randomly divided into the model group and the HJR group. Other rats were recruited as the normal control group. After 12 weeks intervention，the retinal vascular morphology was observed by using trypsin digestion. The expression of VEGF protein was examined by Western-blot. The expression of VEGF, Ras, Raf-1, ERK mRNA in retinas of rats was examined by Real-time PCR.Results:Compared with the normal group, capillary density and the ratio of endothelial cells to pericytes increased in the model group (P<0.001). VEGF protein and VEGF mRNA, Ras mRNA, ERK mRNA expression increased(P<0.05), Raf-1 mRNA expression increased(P>0.05). Compared with the model group, capillary density decreased in the HJR group (P<0.01), and the ratio of endothelial cells to pericytes decreased (P<0.001). VEGF protein and VEGF mRNA, Ras mRNA, Raf-1 mRNA, ERK mRNA expression decreased(P<0.05).Conclusion:HJR could obviously restrain the proliferation of capillary and endothelial cells. The effect is mediated by down-regulating expression of VEGF which is achieved by inhibiting Ras/Raf-1/ERK signaling pathway.