Abstract: 【Purpose/significance】To establish a public opinion transmission model comprising susceptible, latent, spreading, and im⁃ mune individuals, based on the characteristics of police-related online public opinion transmission and WeChat's communication mode.【Method/process】Individuals in WeChat's social network are treated as agents. Using cellular automaton principles, a policerelated online public opinion transmission mechanism is built. The model simulates public opinion evolution considering the diverse transmission features of police-related public opinion and individual agent differences, and analyzes key factors affecting public opin⁃ ion diffusion.【Result/conclusion】The spreader's influence, the credibility of public security organs, and the spreader's exit mecha⁃ nism play key roles in public opinion transmission. Notably, if 30% of the susceptible population trusts public security organs, public opinion spread can be effectively curbed.【Innovation/limitation】The study innovates by developing a cellular automaton-based model of police-related public opinion transmission on WeChat and introducing mechanisms like "loyal followers" to reveal key factors in public opinion transmission. However, it falls short in exploring individual differences in public opinion networks. Future research will delve into individual differences to achieve precise modeling of crowd behavior, offering decision support for relevant departments.