To solve the problems of high transmission delay and low forwarding efficiency in the Routing Algorithm based on Daily Routines（RADR）in opportunistic social networks

an Efficient Community-based Routing Algorithm is proposed（ECRA）.The algorithm only selects the neighbor nodes which are in the same community with message destination node to calculate the node’s important degree.The algorithm uses topological connections to intercept the encounter node.If there exists node which has higher node’s importance than the encounter nodes neighbor

the message is transmitted to the encounter node neighbor nodes by the encounter node.Theoretical analysis and simulation results show that ECRA outperforms existing RADR and the correlation algorithms in terms of delivery ratio

average end-end delivery delay

relay ratio and average storage time.