Based on the complex problem of gas control and temporary hole sealing in coal mine, theoretical study of the characteristics of the new hole packer was conducted, and the theoretical sealing effect formula of hole packer was derived. Apart from the characteristics of the hole packer, three factors that influencing the sealing effect were put forward, that were borehole inclination angle, working pressure and borehole diameter. The theoretical analysis showed that the sealing effect decreased with the increasing of borehole inclination angle, increased with the increasing of working pressure and decreased with the increasing of borehole diameter. The test supported the theoretical results, and provided theoretical basis for temporary sealing hole in mine.