Abstract: With the increasing penetration of distributed generators, the operation of distribution networks is facing the challenge of strong random fluctuation of source and load. Soft open point（SOP） and distributed energy storage system（DESS） can realize the flexible adjustment of power flow from space and time, respectively, and improve the operation flexibility of the distribution network. A bi-layer planning model of SOP and DESS based on spatiotemporal characteristics is established. The upper layer is the siting and sizing layer, which considers the system economy and takes the minimum annual comprehensive operation cost of the distribution network as the optimization objective. The lower layer is the operation optimization layer, which takes the minimum sum of the distribution network loss cost and voltage deviation as the optimization objective. A set of nodes to be installed in the planning scheme is determined by community mining algorithm and improved load moment method. The hybrid algorithm of adaptive particle swarm optimization and second-order cone programming is used to solve the planning model. The results of example analysis and comparative verification through the IEEE 33-bus system show that the joint access of SOP and DESS can effectively improve the spatio-temporal distribution of distribution network voltage and has the lowest operation and installation cost.