Abstract:The genetic diversity of Quercus aquifolioides population located at different altitudes (2 750~3 500 m) of Jade Dragon Snow Mountain in the northwest of Yunnan Province was investigated with amplification fragment length polymorphisms (AFLPs) markers.The results showed that the ratio of polymorphic loci was 100%.Shannon diversity index I was 0.54 and the Nei’s gene diversity index He was 0.37,indicating that the Quercus aquifolioides had high genetic diversity at species level.I and He wereagreed,indicating that the genetic diversity of 6 populations varied with altitude gradient.The genetic diversity from 3 050 m to 3 350 m was high.The genetic diversity of 2 7502 900 m and 3 500 m group was decreased.Results of the genetic differentiation of Quercus aquifolioides Gst (0.089) and AMOVA analysis (Phist = 0.110) showed that there was a low level of genetic differentiation among populations.Gene flow among population was 5.12,suggesting that high gene flow may be a main factor leading to high levels of the genetic diversity among populations.