The typical steppe of Inner Mongolia,which lies within sensitive area of the global change,is the important ecological barrier against sandstorms in China,and is one of the important energy strategies in China for the abundant mineral resources.In order to discuss the influence on the ecological security induced by economic and social development,this paper took Abag County as the research example.The pressure index of the ecological security was introduced on the basis of ecological footprint methodology,aiming at assessing the state of ecological security as well as the magnitude of each influencing factor by the principal component analysis(PCA).The results showed that the pressure index of ecological security had grown up nearly 3.5 times higher with the obvious increase of ecological footprint and small change of biocapacity from 2001 to 2010;which led to a state of unsafe in terms of ecological security in Abag County in 2010.The principle influencing factors such as the per capita GDP,the per capita fossil energy consumption,the proportion industrial output value taking up total output value of production,fixed asset investment and urbanization rate are positively correlated to pressure index of ecological safety,meanwhile,the number students of ten thousand and pasture grazing capacity and precipitation showed a negative correlation.The results could be beneficial for providing the local government the references on typical steppe ecological management.