Abstract: Objective To explore the effect of magnesium and β-carotene(β-c)and their mixture supplementaion on the glucose and plasmalipid metabolism of rats with type 2 diabetes mellitus(DM).Methods Rats with tyep 2 diabetes millitus induced by STZ were randomly divided in to DM group as reference,magnesium group,β-carotene,and normal group as control.After 8 week,blood glucose(GLU),trig lyceride(TG),high-density lipop rotein(HDL),low density lipoprotein(LDL)were determined and the indexes of insulin resistance(HOM A-IR)were calculated.Results After 8 weeks,intervention,the levels of blood glucose in magnesium group,β-carotene,and the imxture of magnesium and β-carotene group were 7.57±5.61,7.85±4.11,and 6.09±3.43,respectively,significantly decreased than that of DM group(13.28±4.11,P<0.05);the levels of serum TG,LDL in magnesium and β-carotene groups were 1.63±0.64,0.29±0.08,significantly decreased than that of DM group(2.65±0.67,0.45±0.16,P<0.05).How ever,the HDL(11.1±0.31)significantly increased than that of DM g roup(0.81±0.10,P<0.05).The HOMA 2IR in magnesium group was 6.64±4.54,significantly decreased than that of DM group(11.94±2.96,P<0.05).The HOMA-IR in magnesium and β-carotene group was 4.95±3.36 with significant decrease(P<0.01).Conclusion Magnesium can improve the blood glucose and insulin resis tance and β-carotene a lone can also improve the blood glucose.The combination of magnesium and β-carotene can improve blood glucose and lipids metabolism and insul inresistance in diabeticrats.