Abstract: In view of the difficulty in gas control of blasting operation in underground coal mines, Tunbao Coal Mine conducted design and research during the construction of winch chamber and gas drainage chamber in the W Ⅱ 02040502 working face. Through optimizing the construction process by using the mine gas drainage system, cooperating with the setting of protection and the building of gas chambers, and innovating the construction method, the gas control is good during the blasting operation. On the basis of meeting the relevant national regulations, the toxic and harmful gas is effectively controlled, while greatly reducing the operation time, ensuring the premise of construction safety, and increasing the work efficiency. No gas overrun accident occurred during blasting operation, which proves that the method is safe and effective.