To explore the axial vibration characteristics of dry gas seals based on the impeller rotor system,based on the characteristics of the dry gas seal structure,the axial vibration model of the impeller rotorbearingdry gas seal system was established and solved by the undetermined coefficient method,and the expression of the axial vibration amplitude of the static ring was derived.The geometric model of impeller rotorbearingdry gas seal system was established,ANSYS Workbench software was used for simulation and calculation,and the influence of the gas film stiffness and exciting force on the axial vibration was analyzed.The results show that the gas film stiffness has little effect on the vibration amplitude of the dynamic and static rings,and the dynamic and static rings have the same vibration frequency and vibration amplitude,indicating that they have high following ability and stable gaps,so as to ensure the stable operation of the dry gas seal.The vibration amplitude of the dynamic and static rings is proportional to the exciting force,which indicates that the excitation force seriously affects the stability of dry gas seal.In order to improve the stability of dry gas seal,the axial exciting force of impeller should be balanced.