Abstract: In order to reveal spatio-temporal differentiation of land covers and its response to climate and topography on annual scale in dry and semi-dry region of northwest China, international universal land cover classification schemes of IGBP, UMD, LAI-fPAR, NPP and PFT were integrated in the study with MODIS land cover datasets (MCD12Q1) and Chinese land cover classification schemes (TEFRS) taken as main data source and reference. Research results showed that: 1) Compared with other 4 land cover classification schemes, IGBP was more suitable to be applied into studying spatio-temporal differentiation of land covers on annual and regional scales. 2) From 2001 to 2009, farmland and rangeland represented increasing trend, but opposite to mash-water body and desert while forest showed increasing or decreasing trend and settlement with no change in 5 land cover classification schemes. Entire land cover classes were inter-transferred and its spatial traverse pattern was highly agreement with regional natural changes and human actions. 3) 6 land cover classes responding to natural condition was closely related with human actions and spatio-temporal distribution of sunlight, temperature, precipitation. The results can be a reference for regional or global LULC research.