Considerdering the grid structure vulnerability,grid exspansion investment cost and the annual operation cost,set the multi-objective power grid planning model.The model combined with economic factors to improve the betweenness index,the gini coefficient for branch electrical betweenness homogeneous evaluation can effectively measure structural vulnerability under the planning scheme.Based on co-evolutionary algorithms(CEA),combined with the fuzzy theory to solve the model.The feasibility of the method is validated by simulation results of Garver 6-bus system. The simulation results show that the presented model is feasible and has important reference value in the grid expansion and planning.