During the construction of gas outburst tunnel, the dynamics of gas outburst are often difficult to master and control; but it is the top priority of the safe construction of gas outburst tunnel. In this paper, the gas flow theory of coal seam is studied; the gas outburst rules of the tunnel are analyzed; the calculation methods and control methods for gas outburst intensity are proposed; meanwhile, it is pointed out that the gas drainage is the most important key to gas outburst intensity control. The study results show that the gas outburst intensity of tunneling face is effectively controlled within 0.5 m3/min and the construction safety of the gas outburst tunnel can be significantly improved by carrying out rational gas outburst control methods.