Western Inner Mongolia Plateau is a sensitive region of global change and its ecological environment is very fragile. This study is based on 2000-2012 MODIS/EVI data in order to study spatio-temporal variation of EVI in this area. We used trend analysis and standard deviation analysis to study vegetation growth of western Inner Mongolia Plateau and its spatial pattern dynamics in recent 13 years. Meanwhile, according to "1 : 1 000 000 vegetation map", we divided the studied area into four regions-desert, steppe, meadow and shrub area for the purpose of researching EVI variation under different vegetation types. Results are shown as follows: Degraded vegetation areas in western Inner Mongolia Plateau are larger than improved vegetation cover. Degraded vegetation areas are mainly distributed in the northern edge of the farming-pastoral transitional zone of Inner Mongolia, including cities like Ulanqab, Hohhot and Baotou as well as valleys of Datong River, Shule River and Heihe River. Improved vegetation areas consist of Hexi Corridor, Hetao Plain and the areas surrounding Abag Banner. Vegetation stability has obvious regional differences from 2000 to 2012. High-fluctuation area is located in southern foot of Yinshan Mountain, Qilian Mountain and areas surrounding Abag Banner. Vegetation areas with high fluctuation are consistent with degraded and improved region. The vegetation in Meadow area and steppe area have degraded seriously in recent years, only vegetation of desert area has a trend of improvement.