Abstract: To solve gas during the production of thick seam fully mechanized caving coal face, especially the exploitation of the early gas control problem, pelvic floor in nanshan coal mine area south of 18-2 second section bottom layer in the process of the implementation of the comprehensive gas control of fully mechanized top coal caving mining faces, for during the preliminary extraction in the extraction from the high technology was studied and improved results show that take active conduction closed drilling filling the leak relay technology such as high drilling field, improve the effect of the gas extraction, can effectively solve the cycle to the old area of a lot of gas emission supply gas pressure on the corner gas overrun problems, ensuring the safety mining face.