To investigate the effects of purple sweet potato flavonoids (PSPF) on blood glucose and lipids levels in diabetic rats.Diabetes was induced by intraperitoneal injection of streptozotocin (STZ, 65 mg.kg(-1)) in rats. The changes of fasting blood glucose and lipids levels in serum and body weight, food and fluid intake of diabetic rats treated with PSPF were examined.Diabetic symptoms were ameliorated after rats were fed with PSPF. The fasting blood glucose (FBG), GSP, TC, TG, LDL-C were decreased and serum HDL-C levels were increased (P0.01) in high, medium dose PSPF groups; while FBG, serum GSP, TG, LDL-C were also improved in low dose group (P0.05 or P0.01).Purple sweet potato flavonoids can decrease the blood glucose and lipids levels in diabetic rats.