Abstract: Aiming at the problem that the small coal pillar roadway is affected by the lateral hanging roof of adjacent goaf in the mining process of kilometer gas mine, taking the small coal pillar roadway of 1208 working face in a mine as the research background. On the basis of engineering practice, this paper introduces the construction technology and method of double end plugging hydraulic fracturing technology in detail, and analyzes the engineering construction effect. The research results show that the double end plugging hydraulic fracturing technology can avoid the existence of fractures and achieve effective pressure maintenance, which is a better method for lateral hanging roof lag; based on borehole peeping, stress monitoring and analysis of mine pressure law, the cracks of surrounding rock are obviously developed after roof cutting, and the front overhanging roof affected by mining has been broken, which shows that the borehole stress meter data is significantly decreased, and the pressure at the lower part of the working face is significantly weakened under the influence of secondary mining, achieving a good effect.