In underground mining, the site of the mining waste dump has a big effect on rock pressure of drifts below. Geotechnical problems are complicated to the extent and cannot be expected in other areas since nonuniformities of existing discontinuous, pores in materials and various properties of the components. At present, it is extremely difficult to develop a program for drifts analysis that considers all complicated factors. However, drift analysis has made remarkable growth for the past several years due to the development of numerical analysis method and computer development, given the situation that it was difficult to solve formula of elasticity, viscoelasticity, and plasticity for the dynamic feature of the ground when the constituent laws, yielding conditions of ground materials, geometrical shape and boundary conditions of the structure were simulated in the past. In this paper, number model method is used to analyse the effect of rock pressure on drifts below the mining waste dump in inclined rock mass layer conditions.