In this paper,by combining the phased and dynamic adjustment characteristics of decision-making in earthquake emergency response,we construct a sequential game model of earthquake emergency decision-making through analyzing the phased game process between the earthquake event and the emergency decision-making body. Then,we introduce the Bayesian theory to determine the disaster level of an earthquake event and realize dynamic adjustment of emergency response plans at various stages. Taking the M7.0 Jiuzhaigou earthquake as an example of the case study,we find that the method is operability and scientific,and it can fully not only satisfy the emergency decision-making body in the earthquake emergency response process,but also adjust the disposal plan according to the stage results and real-time information in order to make different decision-making suggestions at the disposal stage more targeted to the needs,which is of great significance in emergency practice.