Abstract: Uncia uncia is one of the rare large species on the brink of extinction in Felidae in the world, and inhabit only the Central Asian mountains. It is said that there are currently only 4500-7300 Uncia uncia surviving. During the period from September 2004 to July 2005, the habitat selection of Uncia uncia was investigated in some mountains in Xinjiang, including the eastern Tianshan Mountains, Beita Mountains, Altay Mounts and Mount Tumor National Nature Reserve. In several months of fieldwork, we got 171 sign samples of Uncia uncia and 123 random samples in total. Five habitat features, i.e., the elevation, topographic features, vegetation type, grazing status and ruggedness, are selected to compare the difference of selectivity of the Uncia uncia habitat selection. The Chi-square goodness-of-fit test and the binomial test are used to check the significance of Uncia uncia habitat selection, and the principal component analysis is used to find the primary factors in in the selection. The result s are as follows : (1) Uncia uncia selected all kinds of the habitat types , especially the elevation , topography , vegetation types and ruggedness ; (2) Ruggedness and the vegetation types are the preliminary factors for the habitat selection. Topography is the secondary factor ; (3) Uncia uncia prefer to inhabit in the rugged habitat s with moderate shrubberies , and they also like to leave signs in valley bottoms rather than hillsides.