Along with the continuous rise of the importance of power systems, the various dangers they face have attracted increasing attention. In order to explore the robustness of power systems, a networked model considering the actual operating mechanism of a power system is established. Based on complex network theory and a methodological principle, a robust analysis method is proposed. The robustness analysis indices of the power system are given in terms of structure and function, respectively, and three failure scenarios of the power system are simulated. Using the IEEE30 network, the analysis method based on the complex network is compared with the system collapse results based on the conventional power flow analysis, and the proposed analysis framework is verified. At the same time, the robustness of the power system is analyzed in detail using the IEEE300 network and the 1000-node network model that meets the characteristics of small world and scale-free characteristics. The results show that the analysis method can comprehensively evaluate the robustness of power systems in various situations, proving the effectiveness of the method. This work is supported by National Natural Science Foundation of China (No. 61773186).