China's railway construction is gradually extending to earthquake prone areas. In order to improve the seismic service life of reinforced soil retaining walls, the seismic performance of various support structures has become a research hotspot. The method of building a full scale model of a new reinforced soil retaining wall for railway by using Flac^3D numerical simulation software was compared with the traditional modular reinforced soil retaining wall, and the seismic performance of the new reinforced soil retaining wall was analyzed. The results show that under earthquake action, the overall deformation trend of the new reinforced soil retaining wall is outward tilt, that is, the horizontal residual displacement at the panel increases linearly with the wall height, and the maximum horizontal displacement occurs at the top of the wall. The acceleration amplification coefficient at the wall panel > the middle area of the reinforced body > the filled soil area after the reinforced body. The overall integrity of the middle and lower parts of the retaining wall is good, while there are differences in the different forms of reinforced soil retaining walls in the middle and upper parts. The horizontal dynamic soil pressure on the back of the retaining wall increases and then decreases along the wall height, and then increases and then decreases, resulting in a sudden change point at the lower part of the wall, which is the maximum value point. The strain distribution of each layer of reinforcement material shows a single peak shape, and the distribution of reinforcement materials participating in the pull-out resistance is relatively uniform, forming a fracture surface form close to the theoretical fracture surface of the "0.3H" method, and H is the height of the wall. The numerical simulation conclusions can provide reference and guidance for the research on the seismic mechanism of new reinforced soil retaining walls.