In view of the two problems in the traditional architectural lighting system that cannot take into account the comfort and energy saving of large-area lighting environment at the same time, this paper introduces the Particle Swarm Optimization (PSO) algorithm and applies it to the lighting control system. By using multiple sensors to collect illuminance information, the information is input into the algorithm, and is optimized by the algorithm. Finally, the system automatically finds the optimal combination of luminous flux. The algorithm can help the interior of the site to be evenly distributed, and it can greatly reduce the lighting loss and improve the energy utilization efficiency while improving the comfort of the building light environment. This paper is verified by DIALux evo software simulation, and the experimental results show that the scheme is feasible.