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<div><p>Purpose</p><p>This study aims to delineate the operating system of a strategic game model involving three core financial actors—government, banks, and guarantee institutions, with a focus on their collective impact on system evolution towards sustainable SME financing.</p><p>Methodology</p><p>Utilizing numerical simulations informed by dynamic equation constraints and optimal equilibrium states, this paper abstracts the strategic behaviors of system constituents, constructing a game model to predict and analyze system evolution within various operational contexts.</p><p>Results</p><p>The simulation experiments reveal the critical role of quality risk information and responsible actor behavior in maintaining low default rates and fostering a sustainable financial system. System trajectories under various scenarios highlight the fragility of the equilibrium and the necessity of concerted, strategic cooperation among all stakeholders.</p><p>Conclusions</p><p>Findings underscore the importance of a cooperative, conscientious approach by government, banks, and guarantee institutions to ensure a robust and sustainable SME financing environment. The study advocates for strategic policy guidance, emphasizing the interconnectedness of institutional roles and their cumulative effect on system stability.</p></div>