Abstract: In view of the serious problem of floor heave of mining tunnel in 5-107 working face of Pangpangta Mine, this paper analyzes the mechanism of floor heave of the mining roadway under the influence of mining, and sets up the mechanical model of floor heave which is affected by mining, and carries out the stress analysis. At the same time, FLAC^3D simulation is used to study the deformation and failure laws of the mining roadway. The results show that the effect of controlling floor heave in mining tunnel is remarkable by the method of excavating pressure relief groove, and the maximum floor heave quantity corresponding to pressure relief groove depth of 0.5 m, 1.0 m, 1.5 m, 2.0 m is 302.6 mm, 256.5 mm, 217.8 mm and 170.0 mm respectively; with the increase of the depth of the pressure relief groove, the maximum floor heave quantity is gradually reduced and the number of roadway pull-down is obviously reduced, which results in very considerable economic benefits.