The annual and monthly change trends of vegetation coverage and their relationship to regional climate change in National Natural Reserves of West Ordos during the period from 2001 to 2013 were analyzed by employing MODIS NDVI datasets in growing season(from April to October)and corresponding climatic variables including monthly temperature and precipitation.The linear trend analysis,coefficient of variation(CV)analysis and correlation analysis were employed in the present study.The results revealed that regardless of the temporal resolution(monthly scale or annual scale),the NDVI in the study area experienced increasing trend over the 13-year observation period.Although the establishment of national natural reserve can improve the ecosystem of the study area,the annual vegetation variation is primarily dominated by the precipitation fluctuation.The correlation coefficient between NDVI and precipitation is 0.66,indicating that precipitation is the direct factor on vegetation dynamics.In spatial pattern,the NDVI in southern,eastern and northern fringe regions of the study area showed the increasing trend,and no obvious trends were observed in central and some of the northern parts.CV analysis further indicated that the annual variability of NDVI was strongly significant,particularly in the southern parts,indicating the low strength to anti-disturbance.The results from the analysis of core area of the study area indicated that the vegetation dynamics experienced increasing trend in core area of Yikebulaga and Qipanjing and showed the decreasing trend in core area of Mengxi and Aerbasi.