Rainfall easily induces water table rising and leads to a variety of hazards. Infiltration and deformation are coupled during rainfall, while most of the current study focused on changes in seepage field and stress field and there are few studies on the water level and its influence factors. Based on the seepage theory, elastic theory and VG model, the two dimensional hydro mechanical model of unsaturated soil slopes was established. The water table rising was studied under rainfall condition based on the hydro mechanical coupled theory. The model considered not only any soil water characteristic curve, but also the variation of the coefficient of permeability at saturation. The two dimensional hydro mechanical model was analyzed through examples, and the coupling effect of water table change was deeply researched. The results indicate that the effects of rainfall intensity, initial conditions, and the saturated hydraulic conductivity have a great influence on the water table rising. The maximum displacement appear above the underground water level, the displacement gradient is bigger below the water table.