Abstract: In view of the serious floor deformation of gob-side entry retaining, it was still difficult to maintain for a long time after floor excavation control. Taking the gob side entry retaining of 3# Coal Seam in Hexi mine as the engineering background, the mechanical failure mechanism of floor heave in gob side entry retaining was summarized and classified by theoretical analysis method, and the control principle of stress guidance in the entry and pressure relief beside the entry was put forward. The results showed that: under the coordinated action of solid coal rib, stress guiding support in roadway and filling body beside roadway, the supporting stress was transferred to the pressure relief groove and gob floor, so as to reduce the pressure relief risk of roadway floor, dredge the supporting stress of roof and floor, reduced the stress concentration of solid coal wall and filling body beside roadway, reduced the damage of supporting stress to floor, and reduced the floor heave. The application of the research results in Hexi mine has certain theoretical significance and reference value for floor heave control of gob side entry retaining under similar conditions.