In this study, the applicability of a three-dimensional (3D) seepage analysis method called “virtual drain model” to landslide was verified to help rationalize a layout plan for control measures in the landslide. The virtual drain model can simulate the effect of drainage boring without meshing them, resulting in saving time and manpower for generating analysis models. The validity of the proposed method was first evaluated by comparing analysis results with those obtained by meshing the control measures in detail for homogeneous ground. The result showed that the decrease in water level and the drainage volume obtained by the virtual drain model were consistent with the results obtained by finely meshing the drainage boreholes, contributing to reducing the analysis time. The virtual drain model was then applied to examine the control measures for the Yuzurihara landslide, and the analysis results were compared with the measurement data to examine its practicability. The results showed good agreement with the average groundwater level for each construction period in the observation boreholes, simulating the decrease in the average groundwater level associated with the deployment of the control work. Using this method for3D seepage analyses thus will contribute to prompt decision-making for construction of control work on site through visualization of an extent affected by decrease in groundwater level.