Abstract: To meet the needs of afforestation in particular natural conditions in Yuanmou's xerothermic valleys, the quantitative selection research of drought-resistant and heat-resistant afforestation species was carried out. Eucalyptus camaldulensis, E. citriodora, E. exserta var. farvula, Acacia acuriculaeformis, A. mangium, A. crassicarpa, A. cunningharmii A. richii, A. cicinata, Leucaena leucocephala, A. suma Buch.tham.ex Wall. Albizia kalkora, Trema orientalis.were selected as test species, the growth of height, diameter and crown mean width were analysed 3 years after afforestation. Based on the relevant data, the selection criterion to select drought-resistant and heat-resistant affrestation species in Yuanmou's xerothermic valleys was worked out, and the quantitative selection criterion was 3.4325. Conversly, using this criterion to test those test species, Eucalyptus camaldulensis, Acacia crassicarpa, E. citriodora, E. exserta var. farvula, A. cunningharmii, A. acuriculaeformis were selected as afforestation species of Yuanmou's xerothermic valleys. The analysis results of height and diameter growth of test species, the method to select drought-resistant and heat-resistant afforestation species were introduced in details in this paper.