The five volumes of Annals of National Medicine in Yunnan contain more than 1040 kinds of ethnic medicines and national medicines experiene that are commonly used by 25 minority nationalities in Yunnan.Among them,there are 147 species of toxic drugs,including five with fatal toxicity,14 with strong toxicity,57 with toxicity,and 71 with mild toxicity.In order to guarantee the validity and safety of national drug use,Yunnan Institute of Materia Medica applied modern science and technology to study the safety,efficacy and pharmacognosy of 30 kinds of commonly used toxic folk drugs contained in Annals of National Medicine in Yunnan.This paper chooses five typical national medicinal herbs Stephania delavayi,Euphorbia neriifolia,Alocasia cucullata,Achillea wilsoniana and Chamaenerion angustifolium,and summarizes their national medicinal and toxicity experience.The results of acute toxicity test showed that the five national medicinal herbs are toxic.The pharmacodynamic experiments showed that S.delavayi has analgesic action,E.neriifolia has anti-inflammatory action,A.cucullata has analgesic and antitussive effects,Ach.wilsoniana has analgesic effect,and C.angustifolium has analgesic and anti-inflammatory effects.