To solve the unevenness of distributions of optical illuminance and power in visible light communication system, a light source layout based on multi-population genetic algorithm is proposed. Taking 15 LED lamps as an example, the position coordinates were optimized under the fitness function related to variance of received power through the co-evolution of multi-populations. The simulation results on Matlab R2016a showed that, after being op-timized, the distribution of power was evener intuitively, the variance of power reached 1.5744 dBm, the illuminance fell in a range between 889 lx and 1009 lx and the uniformity ratio of illuminance was 91.73%, all of which were better than those of the layout optimized by traditional genetic algorithm and the rectangular layout optimized by mul-ti-population genetic algorithm. This experiment provides a feasible solution for optimizing the visible light commu-nication system so that users can have a more comfortable communication trip in this system.