This study is conducted to study the influence of computer virus spread on the security situation of network systems. It analyzes the relationship between the SIR epidemic spread model and computer network security and proposes an SIPM model for network security situation prediction. Specifically, the SIPM model adds the memory function of nodes for different virus propagation, supports the independent propagation of multiple viruses in the network at the same time, and improves the dynamic propagation equation on the basis of the SIR model. It allows the independent setting of the infection ability of viruses to different device nodes and that of the resistance of device nodes to different viruses, which is closer to the real network environment. The experimental analysis uses a typical campus network architecture for simulation, and the results show that the model can analyze and predict the network security situation from many aspects.