The effects of the Evodiae fructus on the cardiovascular function were assessed in spontaneously hypertensive rats, and isolated preparation of spontaneously hypertensive rats aortic strip. In spontaneously hypertensive rats, intraperitoneal administration of methanol crude extract of Evodiae Fructus (0.5mg/kg) lowered aterial blood pressure which lasted for at least 4 hours. The hypotensive effect of Evodiae Fructus was more stronger with ${alpha}-adrenoreceptor$ inhibitor(Phentholamine) and it was not affected by ${eta}-adrenoreceptor$ inhibitor(Propranolol). The hypotensive effect of Evodiae Fructus was abolished by NAME. It is suggested that the hypotensive effect of Evodiae Fructus may be concern with endothelium-derived relaxing factor and it may be mediated through NO synthesis. Evodiae Fructus showed a vasorelaxing effect on denude aortic strip. It is suggested that Evodiae Fructus has a direct relaxing effect on vascular smooth muscle cells. Judging from above results, it was proved that hypotensive effect of Evodiae Fructus. The mechanism of hypotensive action may be concern with endothelium-derived relaxing factor and direct relaxing effect on vascular smooth muscle cells. Therefore, it is suggested that Evodiae Fructus is applicable to hypertension.