Abstract: In order to improve the routing algorithm efficiency of the structured peer-to-peer overlay networks, a new DHT-based CSSP algorithm was presented with lower maintenance over head and longer route. A short routing table was defined at constant level to record L cache nodes' fingers, one super node finger and one successor node finger. The algorithms maintaining the route table for node entering/exiting were presented, as well as the distributed election algorithm for super node that could cache all of the nodes. And the cache-nodes, super-node and successor-node ensure the high performance of the CSSP. Compared to the performance of such typical algorithms as Chord and Pastry, the CSSP algorithm greatly improves the performance in regard to routing table maintaining, routing hops, fault-tolerance and network churning when nodes are entering or exiting the CSSP P2P system. Simulations and analysis showed that the CSSP is an efficient route algorithm though some problems are to be studied further.