Abstract: China is a big country with broad vegetation cover and superior natural environment. As time changes, however, ecological system of part areas is seriously destructed, so it is very important to research on the change of spatial pattern of vegetation. Horqin district of Tongliao, located in Inner Mongolia, is taken as an example in this paper. By employing theories of time series, average method and interpolation method, and according to MODIS remote sensing data from 2004 to 2013 in the area, we analyze the spatial and temporal variations of NDVI in Horqin district, and conclude the vegetation cover in the district in the recent decade: 1) vegetation cover of the district shows tendency of increasing, with the increasing rate of 0.033/a, and good vegetation cover is in the following years: 2005, 2010, 2011, 2012 and 2013; 2) vegetation cover of west Liaohe river watershed is the highest among the whole Horqin district; 3) summer is the largest contributor to vegetation cover, with the increasing rate of 0.002 8/a. The results offer reference for theoretical study and decision making of ground ecological environment in Horqin district.

Key words: MODIS Data, Horqin district, vegetation cover, NDVI, spatio-temporal analysis, mean annual rate of change