Abstract: Abstract :analyzed the drilling hole gas drainage effect (2225 workface across seams, K2 air way lay out drilling field, pump K3b coal seam gas across seams), it is found that hole sealing technology directly affects gas drainage. The paper, based on the former technology and combined the context conditions, put forwards a newer improvement project of conveyance road (includes drilling layout, sealing material and depth, grouting time, pre-plugging depth) and tested. Adopted the new project, the cost and drilling pressure relief time rise a little, but pressure –relief gas drainage increase a lot, which makes that the drilling field pre-pumping concentration now is always 4.4 times of former one. The test result showed that it has a great guidance to improve drainage efficiency in the site.project of return airway and conveyance road (includes drilling layout, sealing material and depth, grouting time, pre-plugging depth) and tested. Adopted the new project, the cost and drilling pressure relief time rise a little, but pressure –relief gas drainage increase a lot, which makes that the drilling field pre-pumping concentration now is always 4.4 times of former one. The test result showed that it has a great guidance to improve drainage efficiency in the site.