Abstract: We use MODIS MOD13Q1(vegetation indices 16-day L3 global 250 m)data to compute cumulative sum of 16 scenes MOD13Q1 data from late May to late September in 2008 and 2007 when the vegetation in growing, convert vegetation coverage, compute the desertification Index and classify. The classification result objectively reflects spatial distribution of desertification in the north area of Xinjiang. Non-desertification area mainly distributes in the mid-high parts of Tianshan Mountain, Altai Mountain and some oasis. The other areas also have varying degree of desertification. Therefore MOD13Q1 data can be efficiently applied to large scale environment change and remote sensing monitoring of desertification process. In the paper, We can access regional temperatures, precipitation by spatial interpolation of DEM,annual mean maximum temperature and annual mean precipitation data gathered in the 37 weather stations. DI and temperature have high positive correlation, while DI and precipitation have negative correlation by correlation analysis of DI, temperature, precipitation.