In this paper, based on the background of the treatment of empty zone, recovery of hidden resources and mining of middle-depth ore body in the mining process of sharply inclined thin vein group ore body, and based on the concept of synergistic mining, a four-fold mining concept is put forward: the mining method is converted from the air field method to the avalanche falling method, the hidden resources are made to cover the rock layer in middle-depth mining, the empty zone is used as a free blasting space for the cutting chute and the bedding layer, and the shallow holes are applied in synergistic manner with the middle-depth holes. And in this way to empty field method to avalanche method mining design and application. Mining practice shows that: the change in mining method effectively solves the problem of safety hazards in the airspace, hidden resources recovery and safe and efficient mining of the middle and deep ore body, greatly increasing the resource recovery rate, providing great help for mine safety, but also for the same kind of mines to deal with similar problems to provide a reference.