Abstract: Guangdougen is generally known as Shandougen. It is a traditional Chinese drug. It can be used as antipyretic, antidote, anodyne or antiinflammation agent. In recent years, some compounds (alkaloids, flavones and a new glycoside) such as cytisine, matrine, oxymatrine, pterocarpin and isoprenyl chalcone, have been isolated from roots of Guangdougen for medicinal purposes. They give effects of antiarrhythmia, anticancer or antiulcer. A recent investigation reveals that the Guangdougen comes from Sophora tonkinensis Gagnep. (syn. Sophora subprostrata Chun et T. Chen) and Sophora tonkinensis Gagnep. var. polyphylla S. Z. Huang et Z. C. Zhou, var. nov. Gnangdougen is geographically restricted to SE. and NW. Guangxi and SE. Guizhou and Yunnan (103-109°E, 22-26°N). They have an ecological preference for limestone regions, very commonly growing in mountains of 500-800 m alt.

Key words: Leguminosae, Sophora tonkinensis, S.tonkinensis var.polyphylla