In terms of the objective receiver being interfered by multiple Global Navigation Satellite System (GNSS) spoofing signals, the problem still exists that the performance of the other spoofing signals is quite poor since the power of a certain path signal among multiple spoofing signals increases. To this end, a novel power control scheme was proposed. First of all, the influence of multiple spoofing power on noise floor was analyzed based on cross-correlation interference of different Pseudo-Random Noise(PRN) codes, along with the performance of acquiring each spoofing branch with the prerequisite for this noise floor. Then an objective function was constructed and the genetic algorithm was utilized to obtain the optimized distribution of spoofing power. The simulation results indicate that the proposed approach can obviously improve the performance of acquiring each spoofing signal compared to the authentic signals on the condition of noise floor increasing less than 10dB. In addition, the proposed approach paves the way for many actual applications in theory.