With the advancement in communication technology, computer network will become important for information exchange. However, the network has the potential therefore the strong security policy is needed for network security ensuring. To prevent the computer network from the virus invasion, the computer network security technology is ensured, having a clear network virus understanding. In this paper, the structural model of network security detection and monitoring system is established in a proactive way, the function of each component is described, and the design model is introduced to conduct comprehensive and effective automatic security detection on the client and each layer of the network, so as to find and avoid the system from being attacked.Result: The observed example shows that the flow rate of information in and out of the network is relatively stable, with few changes, and the rate of change is close to zero per unit time. In the case of network attack, the amount of data flowing into the target network is far more than the amount of data flowing out of the network.Computer security technology is used to improve the security of the network and prevent network virus from attacking the computer network.