Yan'an City was chosen as one of the pilot zones to carry out the Return Grain to Green Program in1999.After more than 10years of implementation of the program,monitoring and assessing the vegetationvariations become one of the important tasks.We analyzed the dynamic changes of vegetation in Yan'an Cityfrom 1998to 2008by applying trend line model and the vegetation coverage model using SPOT/VGT NDVIdata with Erdas and ArcGIS platforms.The results showed noticeable increases of NDVI in most parts ofYan'an City,in which 21.27%of the total area of the study site had significant increase and 61.46%had medium increase.Spatially,northern part of the city showed higher vegetation cover than the southern part.The average coverage of the entire city is 0.52.Between 0°～35°slope gradient,more than 75%showed significant or intermediate improvement in each slope class,especially the class of 15°～25°slope,which accounts for 35.8%of the total area of the study area.