On online social media platforms, the cross-influence of multiple interested subjects including government and online media on public opinion dissemination determines the direction of the evolution of public opinion in emergencies. An accurate grasp of the game evolution of the behavioral patterns in decision making of multiple subjects can increase governance effectiveness and improve the solutions to emergency challenges in public opinion for the purpose of maintaining social order and stability. This paper analyses the best decisions made by each subject in different scenarios by establishing a multi-subject game model of public opinion in emergencies and simulates the game evolution process of public opinion behavior among the government, media, and opinion leaders by using evolutionary game theory and Python tools in order to verify the decision making behaviors and game outcomes of the subjects in different scenarios. Evolutionary game theory can effectively analyze the interaction mechanism of multiple subjects in public opinion under emergency situations, revealing the evolution process of behavior of multiple subjects in public opinion under different conditions.