Abstract: Elemental abundance values estimation of the exposed crust in southern-central Inner Mongolia by means of large-scale sampling in the region, is a basic work for model establishment of the crustal composition. It can also provide the background values for geochemical exploration. The study area includes two tectonic units, respectively northern margin of Inner Mongolia Axis and the Central Inner Mongolia Orogenic Belt. Trough weighted values method, we've estimated elemental values of 10 major elements and 40 trace elements. The estimated values are proved reasonable by surface heat flow value, and average seismic wave velocity and elements ratios. The estimated average chemical composition of the exposed crust of Inner Mongolia belongs to granodioritic, which is agreed by most researchers. Through comparison with global average composition, the exposed crustal elemental abundance values of Inner Mongolia are similar to the average values. From the diagrams of trace and rare earth elements and comparison with the elemental abundance values of eastern China, we conclude that there is strong crust differentiation and accretion of the whole southern-central Inner Mongolia.