To observe the effect of New Huoluo Xiaoling Dan (NHLXLD)on aorta pathological changes in ApoE Knock-out mice and the expressions of Transforming Growth Factor beta (TGF-β),and to explore possible mechanism of anti-AS．Methods:AS model was induced by high lipid diet in ApoE knock-out mice.Forty five ApoE knock-out mice were equally randomized into 3 groups， including control group(CG),western medicine group (WMG) and traditional Chinese medicine group(TCMG).Ten C57BL /6J mice were also prepared as blank group (BG).During modeling,BG received no intervention;CG took normal saline 0.3 mL daily;TCMG was treated by NHLXLD 9.67 g/kg.d,and WMG was administered avarstatin 3.33 mg/kg.d.The treatment lasted for 13 weeks with gastric lavage once everyday.Then the aortic roots were taken for HE stain and the mＲNA levels of TGF-βof each group were assayed．Results:Atherosclerotic plaques were observed obviously in the aorta of CG mice with overwhelming formation of foam cells, lipid core and a large number of macrophages infiltration．There were visible AS plaques on WMG aortic wall;plaque area was significantly lower than the CG;plaque area in TCMG was significantly reduced with the more smooth aortic endometrium. The TGF-β mRNA expressions of CG were lower than BG(P<0.01);The TGF-β mRNA expressions of WMG and TCMG were higher than CG(P<0.05 or P<0.01).While the TGF-β mRNA expressions of TCMG were higher than WMG, but the difference was not statistically significant (P>0.05).Conclusion:NHLXLD suppressed immune inflammatory response in a certain extent by increasing protective factor TGF-β on anti-AS.It might be one of the possible mechanisms preventing the formation of AS plaque．