The invention discloses a B2G and V2G power distribution network power control system and method based on genetic algorithm. The system comprises a control center for data interaction with the power distribution network, a distributed power supply, an out-of-service battery pile and an electric vehicle, wherein the control center is electrically connected with the electric vehicle through a charging pile; and the charging pile is electrically connected with the out-of-service battery pile and the distributed power supply separately. The control steps are as follows: 1) the state information of the power distribution network, the electric vehicle, the distributed power supply and the out-of-service battery pile is collected; and 2) the output plans of the electric vehicle and the out-of-service battery pile are worked out based on genetic algorithm, and output is controlled according to the output plans. By virtue of the power control system and method, dispersity of the V2G space is overcome, and increment of valley power market is increased; by performing comprehensive control calculation on the out-of-service battery pile and the electric vehicle, the out-of-service battery pile and the electric vehicle can be used as backup capacity of the distributed power supply to smooth the grid connection of the distributed power supply; and in addition, the optimization searching characteristic of the improved genetic algorithm can be made into full play, new energy utilization rate can be further improved, and the operating economy of the power grid is optimized.