Abstract: Intrusion Detection is a newly developed area of network security. The main issue in this area is how to pick-up and analyze the information which contains abnormal network behavior characteristic. In this paper, basing on the research of CIDF and the implement strategy of intrusion Detection System, we design a component-based Intrusion Detection System, which has good distribute and scalable ability. It combine the network-based IDS and host-based IDS into a system, and provide detection, report and respond together.