This research records the ethnobotany plants of Pingtung County Laiyi Paiwan tribe. It has 98 families and 308 species which includes Pteridophyte, Dicotyledon and Monocotyledon. After interviewing 21 local elders, we know that there are 32 families and 47 species of Paiwan medicinal plants which can cure disease like beverages, dermatosis, muscles ache, intestinal and stomach trouble, headache fever, eye illness, cardiovascular disease, department of gynecology, tooth problem and others. The medicinal plants not only take down its Latin name, Chinese name and Paiwan name but also record its apply portion, method and curative effect. For the items of illness curativeness, the highest factor of informant consensus (FIC) 0.92 is department of gynecology, but dermatosis have the most big percent (44.68 percent) of species. Evaluate medicinal plants by diversity index, We can get the value 1.56 of Shannon diversity index. Moreover, the Kreb’s Ecological methodology program was used to calculate the expected number of species
and to figure the rarefaction curves.