The invention discloses a secondary hole sealing method for treating a broken area after extraction of a crossing hole, and belongs to the methods for improving gas extraction concentration in a bedding hole. The secondary hole sealing method is especially suitable for the broken area after the extraction of the crossing hole. The bedding hole is sealed for the first time, and a first-time drilled hole sealing section is formed. Under the action of air pressure of an underground air compression system, a solid particle conveyor conveys solid particles into the bedding hole through a material blowing pipe. The underground air compression system is connected with the material blowing pipe, and air is compressed into the hole for a while. In the process of blowing the solid particles into the hole, the solid particles initially plug the fractures, caused by the crossing hole, of the broken area after the extraction around the bedding hole, and hole air leakage is reduced. The air is compressed by the underground air compression system through the material blowing pipe, the solid particles in the hole are further blown into the fractures of the broken area after the extraction, then the hole air leakage is reduced, the bedding hole high concentration gas extraction period is prolonged by more than one month, the hole use ratio is improved, and coal recovery safety is guaranteed.