Piled retaining wall is a new type of railway retaining structure in China. In current design, the retaining wall, the beam and the piles are assumed as independent components. Both the mutual action of retaining wall, piles and beam and the influence of the soil or rock foundation on the structure are not fully considered, so that there are some limitations in the current design method. In this paper, using field observation and three-dimensional finite element analysis, the lateral earth pressure on the wall back, the stress distributions and the forces of the reinforcements in the beam and the pile were studied. The simulation results were in good agreement with the field observation data. These results revealed that the tensile stresses were very small and the stresses were positive in most zones in the beam and the pile. It can also be found that the tensile stresses or forces in the beam and pile obtained in this study were much smaller than those obtained using the current design method. This clarified that the current design method used for the beam and the pile was very conservative and it should be optimized to consider the effect of the foundation on the whole structure and the interaction among the different components.