Abstract: The COVID–19 pandemic was selected as a retrospective case study. Based on the analytical framework of the Theory of Planned Behavior, a theoretical model was established from the dual perspectives of policy intrinsic characteristics and external implementation environments. Using 510 retrospective survey datasets, structural equation modeling was employed to empirically analyze the underlying mechanisms influencing public policy compliance intention.The results indicate that significant positive influences on public policy compliance intention are exerted by key factors including the intrinsic characteristics of epidemic prevention policies, external implementation environments, public behavioral attitudes, and subjective norms. Furthermore, behavioral attitude is found to play a critical mediating role between policy characteristics, external environments, subjective norms and compliance intention, with the mediating pathway from policy characteristics through behavioral attitude demonstrating particularly prominent effects. Based on these findings, scientific decision-making is recommended to be developed across multiple dimensions to enhance policy compliance, including the optimization of policy design and implementation procedures, improvement of external environmental conditions for policy execution, reinforcement of positive guidance for public behavioral attitudes, and advancement of research data mining and application. This study not only reveals the formation mechanism of policy compliance intention during major public health emergencies, but also provides valuable theoretical support and practical guidance for improving the emergency management policy system for future public health crises.