In order to effectively improve the safety of bus driving and reduce the incidence of accidents, and to clarify the role of driver-passenger (hereinafter referred to as driver-passenger) conflicts on the occurrence of bus accidents. The causality of accidents was analyzed through the system dynamics causality circuit, and the relevant factors were explored that trigger accidents and the development and evolution of accidents. And the different effects of conflict suspension and continuation on accidents occurrence were compared and analyzed from the micro perspective with the help of the differential game. The results indicate that both drivers and passengers can be initiators of accidents, but drivers have more factors that can cause accidents than passengers and are more likely to cause accidents. When a driver or passenger develops a feeling of dissatisfaction, that feeling can have an impact on both his or her own emotions and behavior and that of the other party. If the conflict between the driver and passenger stops within a certain period of time, it will reduce the risk of accidents. However, if the conflict persists, this kind of emotions and behaviors of both parties will cyclically affect each other, causing a cycle of cumulative emotional reaction levels on both sides, leading to escalation of the conflict ultimately leading to an accident.