Abstract: In view of the special circumstances of Xieqiao Mine 1242(3) working face, such as the extremely long time taken to dismantle and the large amount of coal left behind after the supporting, based on the spontaneous combustion condition of coal seam, the causes of spontaneous combustion of residual coal in 1242 (3) working face are analyzed. According to the actual situation of the site, the comprehensive fire-fighting technologies, such as the injection of LFM to isolate air leakage in goaf, grouting fire prevention technology for full coverage of goaf in roof drilling, grouting fire prevention technology for upper corner pipe, liquid CO₂ injection and nitrogen injection, are adopted. Practical results show that CO volume fraction in goaf is effectively controlled at 20×10^-6, effectively ensuring the smooth removal and sealing of working face.