It has been reported that administration of Ginseng powder to the Guinea pig reduces anaphylactic shook induced by horse serum (Lee, 1939). However, Lee et al. (1960) and Paik et al. (1976) have demonstrated that Ginseng increases capillary permeabilites and histamine release from the mast cell. These facts suggest that Ginseng acts directly on the bronchial muscle causing it to dilate. Recently, a number of investigators(Kidakawa & Iwasiro 1963; Takagi et al. 1973) have reported that Ginseng reverses acetylcholine- or histamine- induced contraction in the isolated Guinea pig ileum. We, therefore, undertook the present study to examine if Ginseng relaxes the spasm of bronchial muscle induced by acetylcholine or histamine. We have also attempted to identify the mechanism of the Ginseng effect. Male Guinea Pig was sacrificed by a blow on the head, The trachea was removed and sectioned with scissors into about 12 rings. After the C shaped ring of cartilage was sectioned the one end of ring was tied to the bottom of the incubation bath and the other end was connected to a force transducer (FTO 3C) to record tension on a Polygraph. When the antispasmodic action of Ginseng effect was first examined in the normal trachea which was not treated by the drug. And then the Ginseng effect was tested in the muscle treated by histamine hydrochloride, acetylcholine hydrochloride or barium chloride. The results indicate that Ginseng alcohol extract relaxes the contraction of isolated tracheal muscle induced by histamine (1μg/ml ~ 10μg/ml), acetylcholine (1μg/ml ~ 5μg/ml) and barium chloride (1.5 mg/ml). The mechanism of this action is in Pa.1 due to nonspecific antimuscarinic and antihistaminic effect and in part by predominant action in the adrenergic β-receptor although the α-receptor is also involved. We, therefore, conclude that Ginseng can be act as a bronchodilator.