Abstract: The saturation line is the lifeline of the tailings pond, and the height of the saturation line has a significant impact on the stability of the tailings dam slope. The seepage state is also an important factor affecting the safety of the tailings pond. In order to analyze the influence of three-dimensional drainage facilities for soft beach in the tailings pond on the saturation line, this paper uses Midas software to establish a three-dimensional model of the tailings pond reflecting its geological structure characteristics based on topographic and engineering survey data. Various numerical simulations and calculations are performed on the tailings pond under different working conditions. The results show that the application of vertical-horizontal drainage measures can significantly increase the distribution range of the unsaturated zone on the dam slope, effectively reduce the total pore pressure in the pond, lower the saturation line, and achieve significant drainage effects. The maximum hydraulic gradient on the slope is smaller than the allowable hydraulic gradient, indicating that the probability of permeability deformation or failure occurring at this time is small, and the seepage stability of the tailings dam body is safe. This study also provides a reference basis for subsequent tailings pond drainage design and three-dimensional seepage analysis.