A total of 40 SPF grade SD rats were randomly divided into control group，DR model group，15 mg·kg^－1 paeonol group and 30 mg·kg^－1 paeonol group；there were 10 rats in each group.Except control group，the rats in other groups were intraperitoneally injected with 55 mg·kg^－1 streptozotocin（STZ） to establish the DR medels.After successeful modeling，the rats in control group and DR model group were subcutaneously injected with normal saline，and the rats in 15 and 30 mg·kg^－1 paeonol groups were subcutaneously injected with 15 and 30 mg·kg^－1 paeonol sodium sulfonate.The rat retina tissue was harvested for real-time fluorescence quantitative PCR （RT-qPCR）， Western blotting， and ELISA assays and HE staining was performed to observe the pathomorphology of retina tissue of the rats in various groups.The human retinal microvascular endothelial cells （HRMECs） were cultured in high glucose （HG，33 mmol·L^-1 glucose medium）. Different doses （0， 5， 25， 50， 70 and 100 mg·L^-1） of paeonol were used to intervene the HRMECs and the HRMECs treated with HG for 24 h， respectively；the cell viabilities and apoptotic rates of cells in various groups were detected by CCK-8 assay and flow cytometry， respectively.The optimum dose used in the follow-up experiment was confirmed.The transfected HRMECs were divided into control group， HG group， HG+NC inhibitor group， HG+miR-802-5p inhibitor group， HG + paeonol （25 mg·L^－1） group，HG+paeonol +NC mimic group， and HG+ paeonol + miR-802-5p mimic group.The expression levels of miR-802-5p in the retina tissue and the cells in various groups were determined by RT-qPCR method，and the association between miR-802-5p and SIRT6 in the HRMECs was determined by luciferase reporter gene assay and RNA co-immunoprecipitation assay；the protein expression levels of silent information regulator 6 （SIRT6）， pigment epithelium derived factor （PEDF） and vascular endothelial growth factor （VEGF） in the retina tissue of the rats and the cells in various groups were determined by Western blotting method. The levels of reactive oxygen species （ROS） and the activities of catalase （CAT） and superoxide dismutase （SOD） in the cells in various groups were measured by ELISA.

Compared with control group， the expression levels of miR-802-5p and VEGF protein in the retina tissue of the rats in DR model group were significantly increased （P<0.01）， and the protein expression levels of SIRT6 and PEDF were decreased （P<0.05）， the ROS level was increased （P<0.01）， and the activities of CAT and SOD were decreased （P<0.05）.Compared with DR model group，the expression levels of miR-802-5p and the expression levels of VEGF protein in retinal tissue of the rats in different dose of paeonal groups were significantly decreased（P<0.05），the expression levels of SIRT6 and PEDF were signifricantly increased（P<0.01），the ROS levels were significantly decreased （P<0.05 or P<0.01），and the activities of CAT and SOD were signifricantly increased（P<0.05 or P<0.01）.The HE staining results showed that the retinal structure of the rats in control group was clear， the cells in the inner and outer nuclear layers were arranged regularly， and no neovascularization was observed； in DR model group， the retinal structure was unclear， the nerve fiber layer was edematous， the inner and outer nuclear layer cells were arranged loosely， and neovascularization was observed； the retinal structures were clear and the cells in the inner and outer nuclear layers were arranged in an orderly manner in different doses of paeonol groups， and the neoangiogenesis was significantly improved compared with that in model group. Compared with control group，the apoptotic rate of cells in HG group was increased（P<0.01）；compared with HG group，the apoptotic rate of cells in HG+paeonol group was decreased（P<0.01）.Compared with control group， the expression level of miR-802-5p in the cells in HG group was significantly increased （P<0.01）；compared with HG+NC inhibitor group，the expression level of miR-802-5p in the cells in HG+miR-802-5p inhibitor group was significantly decreased（P<0.01）.The results of luciferase reporter gene assay and RNA co-immunoprecipitation assay showed that SIRT6 was a target gene of miR-802-5p.Compared with control group，the expression levels of SIRT6 and PEDF proteins and the activities of CAT and SOD in the cells in HG group were significantly decreased（P<0.01），and the expression level of VEGF protein and the ROS level were significantly increased（P<0.01）；compared with HG group， the expression level of VEGF protein in the cells in HG+miR-802-5p inhibitor group was decreased （P<0.01），the expression levels of SIRT6 and PEDF proteins were increased （P<0.05），the ROS level was decreased （P<0.05）， and the activities of CAT and SOD were increased significantly （P<0.01）.Compared with HG group，the ROS level in the cells in HG+paeonol group was decreased（P<0.01），and the activities of CAT and SOD were increased（P<0.01）；compared with HG + paeonol + NC mimic group， the ROS level in the cells in HG + paeonol + miR-802-5p mimic group was increased （P<0.05）， and the activities of CAT and SOD were significantly decreased （P<0.01）.

Paeonol may improve the DR progression through the miR-802-5p/SIRT6 axis.