In order to further improve the optimal allocation of power system resources, strengthen the coordination among voltage levels and reduce the economic cost of power grid operation, this paper extends the optimization of single-voltage distribution network structure to two-voltage level and proposes a two-voltage level distribution network reconfiguration optimization method. Taking active power loss, voltage deviation and load balance as the objective functions, while satisfying the operation conditions of each voltage level power grid, coordination constraints such as power supply reliability constraints of each voltage level and line load rate constraints are introduced, and a cuckoo search algorithm is used for optimization. Considering its slow convergence rate and convergence rate in the later stage, the simulated annealing algorithm is introduced to improve the global and local search ability of the algorithm. The example shows that the method proposed in this paper is feasible and effective. This work is supported by National High-tech R & D Program of China (863 Program) (No. 2015AA050101).