Abstract: The gas extraction effect largely depends on hole sealing method and hole sealing quality. Aiming at the insufficient sealing depth and weakness of sealing materials of the existing sealing technology in Qinan, improvement measures were put forward for the exiting sealing technology. Through increasing sealing depth and adopting new sealing materials, the measures avoided short circuit air flow, reduced the consumption of negative pressure in pipeline, and made the gas extraction concentration increased by 25%~50%, eventually improving the production efficiency, and providing security for later coal mine production.