The new geographical distributions of three species in Adiantum L,A.meishanianum,A.sinicum,and A.menglianense are recorded in this paper.A.meishanianum is found in Xishuanbanna and Puer,Yunnan,A.sinicum in Shiping,Yunnan,and Yanyuan,Pingshan,Dukou and Leshan,Sichuan,and A.menglianense in Baise,Guangxi,and Xishuanbanna,Chuxiong and Yuxi,Yunnan.The diagnostic characters are given between these three species and their respective relatives.Neighbor-joining tree of Ser.Caudata(including eight species,without A.soboliferum) based no rbcL gene is provided.A complete key of Ser.Caudata(including nine species) is also provided.