In the power system, the problem of information security is very important, especially with the integration of information system and power system in depth, the formation of a real-time perception, dynamic control and information services such as multi-dimensional heterogeneous complex system. At the same time, the network attack on the communication part of the cyber physical system will have a serious impact on the physical grid. This paper analyzes the information security problems faced by the power system, classifies the network attacks by attacking the target, and summarizes several typical attack scenarios; Then compare several main network; Comprehensive safety assessment of cyber physical system. Finally, the research of cyber physical power system is prospected