Abstract: Under the background of emission peak and carbon neutrality,the coordinated optimization planning of transmission line and energy storage is beneficial to the efficient and economical delivery of renewable energy. A portfolio optimization model based on conditional value at risk is used to describe the risk cost of transmission line and energy storage planning scheme under the uncertainty of renewable energy output and load demand.Thus,the coordinated optimization planning model of transmission line and energy storage is established for the renewable energy centralized delivery area,considering the effect of grid structure and power peak regulation on the local consumption and outside delivery of renewable energy. Based on multi-day coordination scenario analysis method,the stochastic programming model with conditional value at risk is transformed into a mixed integer linear programming model. The case study is presented to verify that the model performs well in measuring the influence of different risk aversion degrees on the optimal ratio of transmission line and energy storage capacity as well as the optimal energy storage site selection,which is conducive to the efficiency and economy improvement on the coordinated planning scheme of transmission line and energy storage.