Objective To observe the changes of plasma lipid,C-reactive protein(CRP) and fibrinogen(FIB) in patients with acute coronary syndrome(ACS)treated with low dose simvastatin.Methods One hundred and twenty patients with ACS were randomly divided into treatment group and control group with 60 cases in each.The patients in the control group were treated with conventional therapy,and those in the treatment group were treated with 20 mg simvastatin per day at the base of control group.The course of treatment was 2 months.Results In the treatment group,the levels of total cholesterol(TC),triglyceride(TG),low density lipoprotein cholesterol(LDL-C),CRP and FIB were decreased significantly and the level of high-density lipoprotein cholesterol(HDL-C) was increased after the treatment(all P0.05).Conclusion The levels of plasma lipid,CRP and FIB can be effectively regulated with the treatment of low dose simvastatin in patients with ACS.