Yongyanggaktang has been used in oriental medicine as a therapeutic agent for cerebral disease and eclampsia for many years. The purpose of this study was to determine the effect of Yongyanggaktang and its exception of Cornu Saigae Tataricae(羚羊角) in YYG about regional cerebral blood flow(rCBF) in rats. 1. rCBF was increased by Yongyanggaktang in dose dependently. 2. rCBF was increased by exception of Cornu Saigae Tataricae(羚羊角) in YYG at high dosages. 3. rCBF was decreased by Yongyanggaktang pretreated propranolol. 4. L-NNA did not affect rCBF. 5.ODQ did not affect rCBF. Above the results. Yongyanggaktang relates to the symphathetic action.