Abstract: To relief the link of mining and roadway excavating and face the strict claim about safety distance of the new Coal Mine Safety Regulations, analyzed the principle of carbon dioxide pre-splitting control of deep hole technology to promote the roadway excavating speed, tested the change law of coal mass parameters at the static state and under the roadway excavating state in N1101 working face of Yuwu Mine, and counted the daily amount of tunneling and gas density of return airway about pre-splitting and after splitting time. Field test dates shown that after splitting, the values of K1 and S had big changes, the daily amount of tunneling was more than 30%~100%, the gas density of return airway was reduced about 16.7%. Proved that this technique could reduce the risk of coal and gas outburst in tunneling faces, speed up the methane desorption speed, improve the roadway excavating speed, ease the problems of replacement of mining and roadway excavating.