Abstract: Objective Based on the massive amount of users social relationship and location information data col-lected from the largest social network website in China-SINA micro-blog,an inter-city geographic so-cial network was built from the aggregated inter-person linkages mapped from virtual space onto thephysical space.Considering about the topological characteristics such as the global and local heteroge-neity,and the spatial interactions among cities,a hybrid geographic backbone extraction approach isproposed which is drawn from the gravity model and information entropy theories.This research canincrease understanding of the structure of urban systems,radiant ability,attractiveness and opennessof cities in the virtual web society.