The aim of this study was to investigate the protective effects of rutin from Buckwheat flowers and leaves (RBFL) on rat experimental diabetic cardiomyopathy and its possible mechanism.This study was performed on a rat model of diabetic cardiomyopathy and the model was established by eating a high-fat diet together with injection of streptozotocin (30 mg/kg) intraperitoneally.Heart weight/body weight (HWI), fasting blood glucose (FBG), plasma level of endothelin-1 and adrenomedullin were measured.RBFL (90 mg/kg/d and 180 mg/kg/d) can decrease the HWI, FBG, endothelin-1 level and increase adrenomedullin level significantly in a dose-dependent manner.These findings suggest that RBFL has the protective effect on diabetic cardiac muscle and the mechanism maybe related to influence the level of endothelin-1 and adrenomedullin.