Objective To explore the influence of new Xuefuzhuyu decotion on IgG,C3 and C4 of peripheral blood in atherosclerosis rats.Methods Healthy adult Wister rats were selected and randomly divided into blank group,AS model group,new Xuefuzhuyu decoctioin low dosage group,the new Xuefuzhuyu decoctioin high dosage group,and positive control group,with 13 cases in each group.Vitamin D3 joint high fat feeding method was adopted to establish atherosclerosis rat model.Medicine lavage began on the first day of experiment.Low dosage new Xuefuzhuyu decoctioin,high dosage new Xuefuzhuyu decoctioin,and atovastatin were administrated to the new Xuefuzhuyu decoctioin low dosage group,the new Xuefuzhuyu decoctioin high dosage group,and positive control group respectively,and distilled water 15 ml/kg · d-1 was administrated to both the blank group and the AS model group.The weight of body was detected each week in each group for regulating the administrated dosage.After medicine lavage was performed for successive 8 weeks,blood was obtained from abdominal aorta for detecting IgG,C3,C4 by immune scattering method.Results The value of IgG,C3 and C4 were (8.110±0.720)g/L,(1.591±0.143)g/L,(0.390±0.33)g/L in the AS model group,(8.000±0.840)g/L,(1.564± 0.132) g/L,(0.396±0.36)g/L new Xuefuzhuyu decoctioin low dosage group,(7.250±0.740)g/L,(1.390±0.150)g/L,(0.326±0.153)g/L new Xuefuzhuyu decoctioin high dosage group and (7.240±0.400) g/L,(1.414 ± 0.104) g/L,(0.330±0.164) g/L in the positive control group,all of which werehigher than the blank group (5.810±0.820)g/L,(0.943±0.124)g/L,(0.330±0.164)g/L with statistically significant difference (P＜0.05).Each value of IgG,C3 and C4 in the new Xuefuzhuyu decoctioin high dosage group and the positive control group were lower than the AS model group and the new Xuefuzhuyu decoctioin low dosage group,with a statistically significant difference(P＜0.05).There was no significant difference between new Xuefuzhuyu decoctioin high dosage group and the positive control group (P＞0.05).Conclusion New Xuefuzhuyu decoction can ameliorate IgG,C3 and C4 of peripheral blood in atherosclerosis rats.Its function was similar to atorvastatin.