Water　induced　loess　landslides　are　closely　related　to　the　rise　of　the　groundwater　level.　Therefore,　research　on　the　response　of　the　groundwater　level　to　irrigation　water　holds　promise　for　revealing　the　mechanism　of　water-induced　loess　landslide.　Taking　Heitai,　Gansu　Province,　as　the　research　area,　a　coupling　model　o　unsaturated-saturated　water　movement　is　established　using　the　HYDRUS-MODFLOW　software.　The　parameters　of　the　model　are　calibrated　and　verified　by　the　Bayesian　parameter　inversion　method　combined　with　field　observations　of　the　groundwater　level.　Finally,　the　change　in　the　groundwater　level　under　different　irrigation　amounts　is　predicted　using　the　optimized　model.　It　is　found　that　a　reasonable　reduction　of　the　irrigation　amount　can　effectively　slow　the　rise　of　the　groundwater　level.　This　research　provides　a　scientific　reference　for　the　development　of　reasonable　irrigation　measures.