【Abstract】 Objective To study the effect of different doses of Zhengan Xifeng decoction on STAT1 mRNA and protein expression in the abdominal aortic vascular tissue of spontaneously hypertensive rats (SHR).Methods 60 male SHR, 24 weeks old, were randomly divided into the model, low dose, medium dose, high dose of Zhengan xifeng decoction and the compound apocynum groups. Twelve homologous male rats (WKY) served as the normal control group. After gavage for 45 days, western blotting and RTPCR were used to detect the STAT1 protein and STAT1 expression in the abdominal aortic vascular tissue.Results Compared with the model group, the STAT1 protein and STAT1 mRNA expression in the normal group, medium dose of herbal medicine group and high dose of herbal medicine group were significantly decreased ( F=833093, sig=0000, P＜0. 01). Conclusion Zhengan Xifeng Decoction can inhibit the expression of STAT1 protein and STAT1 mRNA in abdominal aorta and may reduce the vascular remodeling by inhibiting the apoptosis of abdominal aorta and reduce the proliferation of vascular cells, which play a role in lowering blood pressure.