The following results were obtained from the observation on the change of plasma cortisol concentration in the experiment of intravenous administration of Haengsoyeum Water Extract in the rabbit. And the effects of Haengsoyeum extract on the contractile force of the isolated guinea pig trachea smooth muscle. 1. In intravenous administration the plasma cortisol concentration increased significantly about 1 hours after with a does of 0.2 ml/kg. 2. In intravenous administration the plasma cortisol concentration increased significantly about from 1 to 3 hours after with a does of 0.4 ml/kg. 3. The contractile response of the trachea smooth muscle of isolated guinea pig to histamine $10^{-4};M$ was significantly inhibited by Haengsoyeum extract. 4. The contractile response of the trachea smooth muscle of isolated guinea pig to acetylcholine $10^{-4};M$ was considerably inhibited by Haengsoyeum extract. 5. The contractile response of the trachea smooth muscle of isolated guinea pig to 5-hydroxytryptamine $10^{-4};M$ was inhibited by Haengsoyeum extract.