When laser communication network transmit information, it is easy to be affected by discrete variables, which reduces the quality of information transmission. Therefore, the optimization method of laser communication network topology under the influence of discrete variables is studied. The initial topological structure of laser communication network is generated, and the influence of discrete variables is analyzed. According to the optimization target of laser communication network topology, the optimization target model of laser communication network topology is established. Multi-objective evolution method is adopted to eliminate redundant links in the topological structure and optimize the topological structure of laser communication network. The experimental results show that the average link length of the optimized network topology is less than 50cm, the energy of communication nodes is more than 48J, and the number of network survival rounds is more than 371. The optimization performance is good, and the redundant paths in the network topology are effectively eliminated.