Kava(Piper methysticum Forst) with a wide range of medicinal uses is a popular herbal medicine in Europe and the United States.The research on this plant，especially the TCM properties，will produce huge economic and social values and promote the long-term development of TCM.The roots and rhizomes of P.methysticum are the main parts for medicinal use.This medicine is warm and hot，bitter and pungent，with tropism to the heart，liver，and kidney meridians.It has the effects of tranquilizing mind，extinguishing wind and stopping convulsions，soothing liver and relieving depression，relieving pain，removing dampness and promoting urination.Accordingly，this medicine can be used for treating restless，palpitations，insomnia，convulsions，rheumatism，thick white tongue coating，and poor urination.