[Objective] To observe the effects of different doses of quercetin liposomes( LQ) on oxidative stress and expression of TGF-β1 in kidney of diabetic rats. [Methods]The model of type 2 diabetic nephropathy rats was established by being fed on high-sugar and high-fat diet combined with intraperitoneal injection of streptozotocin( STZ). Then type 2 diabetic rats were randomly divided into six groups: diabetic model group( group DM),low level of LQ group( group LQ-L),medium level of LQ group( group LQ-M),high level of LQ group( group LQH),positive control group( group aminoguanidine,AG) and control group( group N). After 8 weeks,the serum levels of total cholesterol( TC),triglycerides( TG),superoxide dismutase( SOD),malondialdehyde( MDA),glutathione peroxidase( GSH-Px) were measured by biochemical methods. Immunohistochemistry and RT-PCR were used to detect expression of TGF-β1 gene and protein in kidney cortex of diabetic rats. [Results]Compared with the group N,the serum levels of SOD and GSH-Px decreased significantly in group DM,while the serum levels of TC,TG and MDA increased significantly and the expression levels of TGF-β1 gene and protein in kidney tissue increased significantly.Compared with the group DM,in each dose group of LQ have improved the above indicators to some extent and the group LQ-M was more obvious than others. [Conclusions] LQ reduces the blood lipid levels,protects antioxidant activity,inhibits lipid peroxidation of DM rats,and then reduces expression of TGF-β1 gene and protein in kidney cortex.