There are shortcomings in the existing vulnerable points identification method for a power system, where the node characteristics, mutual influences of power transmission between nodes and the node voltage constraints are insufficiently considered. Thus a novel vulnerable point identification method based on a complex network combination and an operation index is proposed. First, from the analysis of power system topology, line parameters, power flow and operating parameters characters, a node degree index based on Laplacian spectral radius, node betweenness index and voltage over-limits index is established. Then, to obtain the combination index, which is applied to identify the vulnerable points for the power grid, the combination weighting method is used to assign complex network and operation indicator weightings. Finally, IEEE30 and IEEE118 bus systems are used to verify the proposed method’s feasibility and rationality. The results show that compared with the reference method, the proposed method’s identification results are more reasonable and have greater relevance for a power system. This work is supported by the Key Intergovernmental Cooperation Project on International Science, Technology and Innovation of the National Key Research and Development Program of China (No. 2018YFE0125300).