In order to improve the efficiency of gas extraction in high gas and low permeability coal seam, taking the application of CO2 displacement to promote the extraction of coal seam gas technology in Shaanxi Huangling No.2 Coal Mine as the engineering background, based on the measurement results of basic parameters of coal and gas, the technical adaptability of CO2 displacement to promote the extraction technology in this mine was analyzed, and the gas extraction concentration and borehole extraction mixing amount before and after the implementation of the extraction technology were compared. The results show that the coal seam in the target area belongs to the type II failure type, the coal quality is hard, the porosity is low, and the effect of pressure injection drilling is good. After adopting CO2 promoting extraction technology, the gas extraction concentration and borehole extraction mixing index increased by 2.25 times and 1.58 times respectively, indicating that the application of CO2 promoting extraction of coal seam gas technology has a significant improvement effect on the extraction effect. It can be combined with CO2 promoting extraction of coal seam gas technology in gas extraction to realize the new mode of gas extraction of ' single pressure group extraction ', which provides a new process method for improving the level of mine gas control.