The Shiyang River Basin is a typical arid inland river basin in northwestern China.It is also a well-known fragile area of water resource and ecological environment,and a sensitive area of climate change.The vegetation in Shiyang River Basin is mostly concentrated in its upstream,and plays an important role in ecological environment of this watershed.Therefore,studies on the spatiotemporal variation of vegetation in the upper Shiyang River Basin and the impacts of changing temperature and precipitation on the vegetation growth are of significance to dealing with climate change,realizing sustainable development of ecological environment in Shiyang River Basin.In this study,the spatiotemporal changes of vegetation growth in upper Shiyang River Basin together with their responses to climate changes were investigated using SPOT-VEGETATION Normalized Difference Vegetation Index(NDVI)and climate datasets from 1999 to 2013.Results reveal that there is an obvious vertical zonal characteristic of the spatial distribution of NDVI.About 81.3% of the study area shows an increasing trend in growing season NDVI.The average NDVI of the study area increases at rates of 7.75% for the growing season(March-November),11.75% for spring(March-May),9.62% for summer(June-August),and 5.98% for autumn(September-November)over the study period.The increase of NDVI in spring and autumn suggests the growing season of the vegetation in this study area has been prolonged.The effects of climate changes on vegetation growth vary with the types of vegetation and seasons,which shows a large spatial and temporal heterogeneity.As compared with temperature,precipitation is the dominant climatic factor affecting the interannual variations of vegetation.