Objective To investigate the effect of astragalus injection on serum oxygen free radical, TGF-β1 and vascular endothelial function in diabetes mellitus.Methods 120 cases of type 2 diabetic patients were selected from December 2010 to December 2014 as the object of study, 2 groups of patients underwent diabetic education and diet, exercise therapy, the control group were treated with metformin hydrochloride tablets, and the observation group were combined with astragalus injection, the contents of SOD, MDA and GSH-PX were compared between the 2 groups.The serum levels of TGF-β1, VEGF, ANG-1 and AOPP were compared between 2 groups.Results After treatment, comared with control group, the serum MDA and AOPP were higher, the GSH-PX and SOD were higher; the TGF-β1 were lower; the VEGF and ANG-1 were higher in observation group ( P <0.05).Conclusion Astragalus injection could improve the function of vascular endothelium in patients with diabetes, reduce the transforming growth factor β1, improving the free radical aggregation state.