In this paper, the effectiveness of the geogrid for reinforcing the trackbed is evaluated via numerical analysis. The finite element analysis is performed for the numerical analysis tool. In the study, the effect of the geogrid on the bearing strength of trackbed is investigated. Two different track systems including the conventional ballasted track and the asphalt underlayment track are adopted in the comparison study. The results show that the conventional ballasted track exhibited better effectiveness than the asphalt underlayment track. Also, better effectiveness of geogrid can be achieved by installing at one third depth of ballast layer from the bottom.