To meet the requirements of a certain high-speed launching device，the design analysis and optimization is performed to the nonlinear motion guideway of the ammunition chain to ensure the smooth delivery of the projectile to the firing position. The design optimization of the guideway is crucial for ensuring the continuity and reliability of ammunition supply in high-velocity and high-precision launch systems. By establishing the equation of the guideway curve and analyzing the curve characteristics at different positions of the guideway，it is found that the design exhibits flexible impact. Spline interpolation is employed for optimizing the guideway curve，and simulation verification is performed to the optimized guideway，and the simulation result meets the engineering needs. A theoretical basis is provided for improving the dynamic characteristics of the guideway and extending its service life.