The invention belongs to the technical field of network virus defense, and discloses a novel computer network virus defensive system. The network virus defensive system comprises an end detection module, a virus monitoring module, an analysis module, a main control module, a virus feature library module, a virus feature matching module, a virus isolation module, a virus searching and killing module, and a repeated-virus-infection-prevention module. The end detection module, the virus monitoring module and the analysis module are connected with the main control module through a circuit line separately; the main control module is connected with the virus feature library module, the virus feature matching module and the virus isolation module separately through the circuit line separately. Through the repeated-virus-infection-prevention module, the regenerating capability of viruses can be eradicated; through the analysis module, botnet viruses or target attack viruses which are targetedaiming at virus attacking objects can be analyzed, searched and killed, and therefore compared with general antivirus software, the novel computer network virus defensive system is more targeted.