Recently more attention is paid to the study of visualization at home and abroad, the application of visualization technology in power grid dispatching automation system is becoming more and more widely, but there is lack of systematic research on visual display method at present. This paper summarizes a set of power system visualization display technology and the methods. The application of visualization technology in power grid dispatching automation system is divided into four levels, the first layer is the graphical data, which fully shows the basic data of power grid operation. The second layer is a hierarchical information, in which the key information is shown initiatively from different levels. The third layer is the information integration, which displays joint correlation information. The fourth layer is the information intelligence, which is to analyze the relationship among various kinds of data and information and to provide auxiliary decision making for dispatch operation. Through the application of visualization technology, the system users can master the current system operation state more conveniently and more intuitively, so that the users can adopt operational control measures more effective and more targeted. This method has been applied in dispatch control centers dispatching automation system in SGCC, Fujian Province and Shandong Province successfully which proves the feasibility and applicability of the proposed method.