The invention discloses an energy storage optimization configuration method for coping with a regional power supply line fault. Firstly, element parameters of a researched electric power system and common energy storage economic technical indexes are collected; secondly, a regional power grid line fault and a power supply recovery process are determined; thirdly, an electric power system operationand energy storage configuration model considering response time of a power generation unit and an important load power supply demand index is built; fourthly, a minimum weighted sum of the total cost of composite energy storage investment, an expected operation penalty after the regional power supply line fault in a full-life period of energy storage and the operation cost is taken as a configuration target; and finally, the model is solved to obtain an energy storage configuration scheme. According to the method, the characteristics of different types of energy storage can be comprehensively utilized, and the power flow out-of-limit problem and the power supply demand problem possibly occurring after a power transmission line breaks down are solved by minimum composite energy storage investment, so that the operation reliability of the electric power system can be guaranteed; and in addition, the sensitivity analysis can be carried out on key parameters affecting an energy storage configuration result through the provided method.