In order to further explore the mining failure law of No.2 coal seam floor in Gequan Mine, determine the depth of floor failure, and better guide the safe production, based on the geological conditions and production conditions of Gequan Mine, through on-site field investigation, theoretical calculation and underground on-site drilling double-embolization water pressure test method were used to comprehensively determine the depth of mining water conduction failure zone of No.2 coal seam floor. Development law of floor water-conducting failure zone was analyzed and summarized, and countermeasures and schemes were proposed. The study provided technical support for the safe production of Gequan Mine.