Abstract: Berberis dasystachya Maxim. represents a prominent and characteristic plant species,indigenous to the Qinghai-Tibet plateau,in order to investigate the regulation effect on glucose and lipid metabolisms and related mechanism of Berberis dasystachya Maxim.powder on STZ-induced diabetic rats,the hypoglycemic and hypolipidemic functions of the Berberis dasystachya Maxim.Fruit powder(BDF)on diabetic rats induced by streptozotocin(STZ)were investigated. Results showed that a decrease in diabetes could be observed after treating rats atdose of 0.4,1.6 g/kg for 28 days.On day 28,compared to MC group,administration of BDF at different dosages(0.4,1.6 g/kg)resulted in an increase in bodyweight of the diabetic rat by 16.29% and 27.02%,respectively;a significant amelioration in blood glucose levels in diabetic rats could be observed,with blood glucose level reductions by 25.17% and 26.93%,respectively(vs. MC).BDF at a dose of 1.6 g/kg caused reduced levels of TC(41.17%),TG(33.52%),LDL(57.30%),VLDL(32.85%)and raised levels of HDL(1.44 times)(vs. MC).Meanwhile,the fruit of Berberis dasystachya M. ameliorated the activities of HL and LPL to lower the lipid levels. It was found that after different dose(0.4,1.6 g/kg)of BDF treatment,the content of MDA was markedly decreased(56.65%,29.87%)in serum in STZ-induced diabetic rats(vs. MC). BDF at a dose of 0.4 g/kg could significantly increase the activity of CAT(88.16%),SOD(17.52%)and GSH(63.43%)in serum,while the BDF at a dose of 1.6 g/kg could markelly raise the activities of CAT(1.46 times),SOD(1.36 times)and GSH(1.45 times)in serum in STZ-induced diabetic rats(vs. MC).It is indicated that the BDF functioned as an effective anti-diabetes component and it may protect the β-cells of the pancreatic islet through attenuating oxidative stress.