Taking the spiral groove dry gas seal for helium medium as the research object,considering the interaction between the temperature distribution,deformation of the sealing rings and gas properties,film thickness,heat generation and other factors,coupling the equations of fluid domain and solid domain,setting the force and thermal boundary conditions according to the characteristics of the seal structure,the thermal-fluid-solid coupling calculation model for the performance analysis of dry gas seal was established.Based on this model,the thermalfluidsolid coupling analysis of dry gas seal for helium was carried out,and effects of different rotating speed and groove depth on seal performance and other parameters were discussed.The results show that there are obvious thermal deformation and force deformation in the range of parameters in this paper,which will cause obvious changes in the gap shape,thus strongly affecting the sealing performance such as leakage.The variation of working condition parameters and geometric parameters affect the flow field,heat transfer and deformation characteristics at the same time,and the sealing performance is affected by the coupling effect of each physical field.The multiphysical field coupling model developed in this paper can be used for performance prediction and auxiliary structure design of dry gas seals for helium and other gas medium.