Objective:Comparing the effect of different doses of simvastatin in lowering the serum lipid.Methods:79 patients were randomized into group A and group B,and were given simvastatin 10 mg*d-1 (group A) and 20 mg*d-1 (group B),respectively for a total of 8 weeks.Results:Comparing with baseline,in group A,TC,TG,LDL-C were decreased by 23.4%,20.0% and 30.7%,respectively (P＜0.01); HDL-C was increased by 17.5%.The content of serum TC,TG and LDL-C was decreased to the normal range in 12.8%,28.2% and 15.4% of the patients in group A.For the group B,TC,TG,LDL-C were decreased by 32.7%,22.8% and 42.8%,respectively (P＜0.01); HDL-C was increased by 13.7%.The content of serum TC,TG and LDL-C was decreased to the normal range in 65.0%,57.5% and 65.0% of the group B patients.Conclusion:Oral intake of 20 mg of simvastatin once a day can effectively reduce the serum lipid.The patients can well tolerate and no obvious side effect was observed in our study.