For investigating floor heave behavior and controlling technique of roadway intersection in deep mine, creep deformation characteristics of floor around roadway intersection was studied by Flac3D and the effects of shear plastic critical value, reinforcement measurement on creep deformation of floor around roadway intersection were discussed. As a result, the creep deformation curve can be divided into two stages including initial creep deformation stage and softening deformation stage, which can explain the case that deformation of roadway intersection is little before a certain time, but then increases at a high speed; only when total shear plastic value exceeds the critical value can second creep stage take place; reinforcement measurement with bolting in roof and ribs has little effect on floor heave, yet exerting pressure against floor can reduce floor heave obviously.