This paper proposes a new mathematical model of distribution network reconfiguration with the purpose of load balancing, i.e. evaluating the load unbalance with the load balance index(LBI). And then it adopts genetic algorithm, takes the states of the switches as the genes of the chromosome for encoding, and through reproduction, crossover, mutation, etc, comprehensively analyses and calculates the optimal proposal based on fitness function, that is the proposal with the least LBI value. At the same time, by comparison, power loss values are calculated when the LBI values are relatively small, and the conclusion is drawn that the power losses are decreasing accordingly as the load becomes more balanced. The proposed approach is tested on IEEE three-feeder, 16-bus system and the results show the proposed scheme for network configuration is valid in improving load and reducing power loss.