Abstract: For the purpose of realizing the anycast communicate more efficiently,the article is proposed an anycast routing algorithm based on Multi-Cores Uni-Directional Shared Trees based on the analysis of advantages and disadvantages about the existing anycast routing algorithm PIA-SM and CBT,and presented the choice strategy of the core nodes and the anycast group members.The experiments show that the algorithm can balance the network and server load,and reduce the transmission delay efficiently under the heavy network load.