Jaeumgenby-tang(JGT) have been used in oriental medicine for many centries as a therapeutic agent of vertigo caused by deficiency of qi(氣) and blood(血). Effect of Aurantii Fructus(AF) take off the phlegm by promoting the circulation of qi, Gastrodae Rhizoma(GR) has effects treating for headarch, vertigo by calming the liver and suppressing hyperactivity of the liver-yang (陽). I investigated whether injection of JGT adding AFㆍGR extract(JTG) affects cerebral hemodynamics [regional cerebral blood f1ow(rCBF), pial arterial diameter(PAD) in cerebral ischemia rats by MCA occlusion method, and I designed to make manifest whether JTG is mediated by adrenergic β-receptor, cyclooxygenase or guanylate cyclase. The changes of rCBF was determinated by laser-doppler flowmetry(LDF), and the changes of PAD was determinated by video microscope and width analyzer. The results were as follows in cerebral ischemic rats; The changes of rCBF and PAD were increased stabilizly by treatment with JTG(10 ㎎/kg, i.v.) during the period of cerebral reperfusion, and pretreatment with propranolol and indomethacin were increased JTG induced increase of rCBF and PAD during the period of cerebral reperfusion. Pretreatment methylene blue was decreased JTG induced increase of rCBF and PAD during the period of cerebral reperfusion. In conclusion, JTG causes a diverse response of rCBF and PAD, and action of JTG is mediated by adrenergic β-receptor and cyclooxygenase. I suggest that JTG has an anti-ischemic effect through the improvement of crebral hemodynamics.