The effect of insulin treatment on fatty liver was investigated in diabetic mice fed with high-fat diet.C57 BL/6J mice were fed with high fat diet for 12 weeks,and then treated with Glargine for 4 weeks.The results showed that during intraperitoneal glucose tolerance test,blood glucose,serum total cholesterol and triglyceride(TG) were significantly lower in insulin-treated high fat group than those in untreated ones(P<0.05).The hepatic histology showed minimal or barely visible fat in hepmic cells along with TG content in liver decreasing by 20.71%. The results suggest that insulin ameliorates hepatic intracellular lipid accumulation induced by high fat diet.