Abstract: The selection of the 10 k V network structure is the key to planning and transformation of distribution network. It is impacted by many factors. In order to establish the network structure target, firstly, the investment cost of the distribution network was calculated on the basis of determining the number of structure frame units. Secondly, combining the comprehensive function of user’s power outage loss, the reliability benefit was measured by utilizing the system average interruption duration index; Then, the objective function of the multi objective programming of the grid structure was established, and the weight coefficient variation method was used to transform the reliability benefit and the cost of investments into the total cost of the unit load power supply. Finally, the optimal network structure under the continuous load density interval was obtained by taking the influence factors of the grid structure as the initial population and the minimum total cost of the unit load as the fitness function, and by using the differential evolution（DE）algorithm. It was verified by examples that the algorithm has fast convergence and high accuracy. It can provide a theoretical basis for the construction of distribution network.