Abstract: With the development of rural electrification, electricity load and consumption of rural power network are increasing. The current voltage pattern can not meet the demand, and how to select better voltage pattern programs become an urgent problem to be solved. Based on rational design of the network structure model, and through calculations of the economic parameters and the cost on the grid, a constrained nonlinear programming model was established, which the objective function is to minimize annual cost of unit power supply area and optimization variable is the power supply radius. Economic comparison between different voltage pattern programs were conducted using the objective value optimized by this model. The results show that voltage pattern of rural power network in our country should be simplified in the future, and medium distribution voltage should be developed to 20 kV and 35 kV, and power supply radius of rural power grid should be adjusted according to the reference values of economic power supply radius.