Abstract: Objective:To study effect of micro-milling on blood lipid level of hyperlipidemia of mice with insoluble dietary fiber from Fructus Crataegi.Methods:Kunming mice were taken as experimental animal, 5%, 8%, 12% crude and micro-milling insoluble dietary fiber from Fructus Crataegi were added feed of the dose group, mice fed a normal diet were served as the normal control group and fed a high-fat diet as the hyperlipidemia model group.After 40 days of administration, serum total cholesterol (TC) , triglyceride (TG) , low-density lipoprotein cholesterol (LDL-C) , high-density lipoprotein cholesterol (HDL-C) and TC, TG levels in the liver of all the rats were examined.Results:Both coarse powder and micropowder of hawthorn IDF could decrease the contents of serum TC, TG, AI and LCI levels on hyperlipidemia of mice, reduce the contents of liver TC and TG, and micropowder effects more apparent.Beside, micropowder of Fructus Crataegi IDF could also reduce LDL-C levels on hyperlipidemia of mice (p<0.05) , coarse powder had no such effect.Conclusion:Micropowder powder of Fructus Crataegi had stronger function of reducing blood lipid.