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As a natural meadow resource,the Inner Mongolia meadow is located within the semiarid area to sub-humid region,and an important livestock raising production base in the northern part of China.However,the meadow degradation progresses as a result of influences such as global warming and human disturbances in recent years.Consequently,desertification has become a problem.Besides,it is argued there is success in greening vegetation by the region as a result of efforts of the Inner Mongolias desertification and sandstorm prevention in recent years.There are four sandy lands in China,and all of them located in Inner Mongolia.One of the sandy lands which in the Xilingole meadow is argued grassland degradation become serious in recent years,and especially noticed by the source of dust for the not only in Beijing-Tianjin Area but also in Japan and Korea.Now the reason of desertification overgrazing and over -cultivation was taken up and policies such as stopping grazing,ecology emigration and afforestation policy are being argued animatedly.To investigate the actual conditions of the environment change,the GIMMS/NDVI (Global Inventory Modeling and Mapping Studies /Normalized Difference Vegetation Index) and MODIS/TERRA data is used in this research to do an analysis of the Hunshan Dake sandy lands vegetation changes over time and space starting from 1981 to 2006.Moreover,to examine the influence that the meteorological element gave NDVI,the temperature and the precipitation data from 1981 to 2006 in the study region according to the decade are analyzed.In-situ investigation was done from 2007 to 2009.And collected statistics data,influence on the vegetation change was investigated from both the impact of climate variation and human activity.Some conclusions are drawn as following: It can be seen from the changing trend of NDVI of the entire region (Hunshan Dake sandy land),it increases in the 1980s and the 1990s,though it decreased in 2000-2001,and after that it recovers a little,the decreasing tendency during the entire period is not admitted.Result of classification of land uses in study area into grassland,cropland,woods,unused ground,water bodies,and urban and village,It doesnt decrease in other land uses,though the changing trend of NDVI shows the decreasing tendency in the village and the urban.It has been understood that the climatological normal precipitation decreases gradually from the southeast part to the northwest,and there is a feature that NDVI has decreased from southeast part to the northwest according to the distribution of precipitation.It shows NDVI have a high correlation with change of precipitation during the growth period,which is thought to be important.Moreover,when seeing according to the land use、the correlation is high in the grassland and unused ground (sandy land),the correlation is high in the western where dryness is remarkable in the region.When remarkable small rain years (1989,2001,2005) NDVI is compared in recent years,it is shown that the decrease was the most remarkable in 2001,and the decrease was few in 2005.This tendency is remarkable in a northeastern [Xilinhaote] city.From In–situ investigation,it is known that vegetation degenerates because of the locust harm generation in addition to dry weather and frequent sandstorms from 2000 to 2001,vegetation recovered by an increase in precipitation and effect of the forbidding grazing policy from 2002 to 2004.