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The fractional vegetation cover (fv) is one of the important indicators to reflect the health of grassland ecosystem. However, fv is influenced by both natural factors such as temperature and precipitation, and human activities such as grazing. The fv estimated by MODIS surface reflectance product (MOD09) was used to analyze the grassland variation in Xilingol steppe. There are four different types grassland in Xilingol steppe, which are temperate meadow, typical steppe, sand steppe and desert steppe. The temporal and spatial variations of those four different types grassland were analyzed in growth seasons (April to October) from 2001 to 2013 by fv. The coefficient of variation (Cv) was used to indicate the changing degree offv during the study period. Moreover, the climate and livestock data were combined to analyze the effects of climate change and human activities on grassland variations. The results indicated that the spatial distributions offv in different years were similar, which were decreased from east to west. However, the interannual variations of the same type of grassland had no significant fluctuations. The yearly Cv variations indicated that 78.66% of the study area was in fragile and very fragile level. The typical steppe and sand steppe were in fragile level, and the desert steppe was in very fragile level, but the temperate meadow was in stabile level. The effect of precipitation onfv was positive and in very significant level. On the contrary, the influence of temperature on fv was negative and not significant. The livestock number had significant effect onfv, and the suitable livestock number should be 39 standard sheeps/km2 in Xilingol steppe.