Aimed at the problem of poor sealing performance and large leakage of dry gas seal system at high speed,a double groove-stepped groove face seal structure was proposed.CFD was used to compare and analyze the sealing performances of single spiral groove,double groove-stepped spiral groove and stepped groove under different pressure and speed.The effects of groove depth and spiral angle on sealing performances were discussed,and the optimized structural parameters of double groove-stepped groove were obtained.The results show that double groove-stepped groove is better than stepped groove and single spiral groove in reducing leakage and improving comprehensive sealing performance.The double groove-stepped groove face seal has the largest stiffness to leakage ratio and the lowest leakage when the groove depth is 6 μm and the helix angle is 18°.Under the condition of high speed and low pressure,compared with the performance of ordinary spiral groove dry gas seal,although the bearing capacity of double groove-stepped groove dry gas seal decreases slightly,the stiffness to leakage ratio is increased by 21.74%,and the leakage rate is reduced by 27.45%.