In order to improve the sealing performance of a dry gas seal with spiral grooves onto its faces(S-DGS), a new type of dry gas seal with its groove outline between S-DGS and a spiral groove dry gas seal with an annular groove(AS-DGS) was presented. The shape of surface grooves of such a new dry gas seal was similar to that of a flying goose, so it was simply named as GS-DGS. The geometrical parameters of flying goose grooves were defined. A two-dimensional Reynolds equation for controlling film pressure between the two faces of such a GS-DGS was set up according to the theory of gas lubrication. The finite element method was used to solve the Reynolds equation. The variation of opening force, leakage rate, axial film stiffness and ratio of film stiffness to leakage with the geometrical parameters of goose-grooves was studied. Optimization of such geometrical parameters was finished according to the principle of getting small leakage while maintaining high axial film stiffness. The results showed that excellent sealing performance could be obtained for a GS-DGS when the width ratio of groove and land was between 0.8 and 1.2, the radial width ratio of the groove was between 0.4 and 0.8, the goose neck groove length ratio was between 0.25 and 0.35, the goose neck groove width ratio was between 0.2 and 0.4, the groove depth to gas film thickness ratio was between 2.5 and 4.0, the number of grooves was between 10 and 18, and the spiral groove angle was between 10° and 18°. © All Rights Reserved.