The invention belongs to the technical field of mining of underground mines, and relates to underground mining method, in particular to a pre-controlled roof mechanization sub-level open stope subsequent filling mining method. According to the method disclosed by the invention, subsequent filling is adopted, mining and filling do not influence with each other, and the process is simple. The methodcomprises the following steps: performing presplitting blasting on two sides of a stope room by utilizing a downwards vertical medium-length hole drilling and blasting method, blasting in sections line by line so as to reduce the influence of the blasting on adjacent pillars; performing roof timbering by a drilling tunnel, and preventing roof caving from smashing ore transfer cars. Compared witha mechanized upward sub-level fill stoping method, the mining method disclosed by the invention has the advantages that the cost of tons of ore is reduced, the mining efficiency is improved, and the production cost is obviously reduced; loss and dilution are small, the ore recovery rate reaches 91.3%, and the problems of mining efficiency, safety and cost of unstable difficult mining beds in the underground mine can be solved.