Aimed at the problems existed in the traditional gas film seal devices with labyrinth seal as the shaft end seal,a new sealing structure of combined shaft end seal was designed.For this combined shaft end seal,the pumping effect was produced by using a special structure,and the axial sealing of fluid reverse pumping was realized.The gas film seal using this new type of combined shaft end seal,with the functions of fluid reversal dynamic pressure pumping in axial and radial direction,has high sealing performance,lower wear and long sealing device life.The ANSYS software was used to establish three dimensional flow model of combined shaft end sealing and to carry out numerical simulation.The results show the special structure of the combined shaft end sealing generates horizontal thrust for the fluid rotating along the screw thread.Fluid pressure is increased after passing through the combined shaft end sealing structure,and a pumping effect is produced to achieve the radial seal.