Abstract: A complete survey on geographic distribution of Paa yunnanensis was conducted in 84 counties of Yunnan Province. The distribution of this species was mapped with GIS tools, based on both the data obtained from this sampling and derived from literatures. The result shows that P. yunnanensis is widespread in 71 counties of 15 prefectures, except Diqing prefecture of Yunnan Province. The altitudes and mean annual temperatures for P. yunnanensis distribution were recorded as 1 400−2 600 m and 11.54－18.50℃, respectively. Based on these features of P. yunnanensis, two possible distribution maps of the species were mapped through software DIVA-GIS 5.2. These maps may forecast the potential distribution of P. yunanensis in Yunnan, providing basic data necessary for further study and protection of P. yunnanensis.