In the information and communication networks, each internal functional unit establishes a functional relationship through information exchange to form a complex networks system. From the perspective of complex networks theory, analyzing the network structure of information and communication system has profound practical significance for deepening the construction of information and communication network and security protection. Using Matlab to simulate the process of attacking information and communication network, it can be concluded that networks which are deliberately attacked paralyze much faster than those which are randomly attacked. Therefore, there are some key communication nodes in large complex networks which should be especially focused on. Correspondingly, some targeted protective measures can be taken to improve the security of the information and communication networks. The measures are as follows: to strengthen the protection of the core nodes, to enhance disaster recovery capabilities, to achieve diversity and accessibility of information communication, to use multilevel network protection, and to develop rapid recovery network repair capabilities.