One-hop algorithms have been proposed to solve the problem of fast queries in structured Peer-to-Peer (P2P) system. The core concept for one-hop algorithms is to maintain a huge routing table, but most of them so far have opted to deal with routing table maintenance with a fixed consuming for peers, in order to keep minimal maintenance traffic at the cost of operating performance. In this paper we introduce the Capability-Aware one hop DHT lookup algorithm for P2P overlay referred to as CAP, a novel one-hop DHT algorithm capable of maximizing the performance under peers' real-time network environments and resources for P2P systems. Moreover, CAP can dynamically form a more efficient dissemination trees with the enhancement of either peers' capability or network environments. Furthermore both our experimental results and formal analyses demonstrate that CAP significantly improves the performances on lookup failure rates and time of event delivery.