Pile sheet wall is a commonly used support measure in landslide control of highways, and the optimization design of its structural parameters is a research focus in engineering construction. Taking the pile sheet wall project of AK0 + 560 ~ AK0 + 660 section of Jianshui (Gejiu) to Yuanyang Expressway in Honghe Prefecture, Yunnan Province as the background, the influence and optimization of three structural parameters of pile embedded length, pile spacing and pile width were studied by combining numerical simulation with grey correlation analysis and orthogonal test design, and finally the stability of the optimized structural parameters under earthquake conditions was verified. The results show that the pile spacing is the main influencing factor, and the correlation between the embedded length and the pile width is similar, which is the secondary influencing factor. The optimal combination of the structural parameters of the pile-sheet wall is the pile embedded length of 15.0 m, the pile spacing of 5.0 m, and the pile width of 3.0 m. Under seismic conditions, the earth pressure at the cantilever section of the anti-slide pile, as well as the displacement and settlement difference of the pile body meet the specification requirements, and the slope stability is good.