Mobile devices in Opportunistic Networks are used and carried by people,whose social behaviors and characteristics can greatly improve the routing performance.However,most routing protocols resort mere to the state information,including the contact history or the social feature of nodes,to assist the relay selections.In fact,nodes vicinity is considered to achieve optimal selection of relay.In this paper,we propose a new method of social group formation and an enhanced social group-based routing in which the relay node is selected based on the vicinity of a node and the social group information together.Extensive simulations on real traces demonstrate the efficiency and effectiveness of the proposed method by comparing it with several existing routing schemes.