In order to improve the sealing performance of bi-directional rotary seal in dry gas seal, the T-groove of dry gas seal was selected as the research object to set up ordered micro texture design. Based on the gas lubrication theory, the Reynolds equation was solved by the finite difference method.The sealing performance parameters were calculated with the speed, pressure, gas film thickness and micro texture depth as independent variables.The results show that the micro texture design can effectively improve the sealing performance.The opening force is increased with the increase of rotating speed and pressure and the decrease of film thickness,and the leakage is increased with the increase of pressure and gas film thickness and the decrease of rotating speed.The change law of sealing parameters of the four micro texture T-grooves with the operating parameters is similar.The sealing effect of radial micro texture arrangement is better than that of circumferential micro texture arrangement,and the sealing effect of composite micro texture arrangement is better than that of single micro texture arrangement.T-shaped grooves with longitudinal and transverse micro textures have the best sealing performance.