Launch vehicles are typically composed of multiple thin-walled sections. While thin-walled structures are well-suited for bearing distributed loads, components such as the motor bracket, strap-on boosters, and vertical columns of rockets are often subject to significant concentrated loads. To effectively transfer these concentrated loads to the thin-walled structure, specific structural components must be designed to facilitate load diffusion. This study investigates the optimization of load diffusion components incorporating stiffeners and skin. Utilizing the finite element method, an optimization framework based on a beam/plate model is established, proposing an objective function that accounts for load diffusion uniformity, structural weight, and stress. The optimization results demonstrate that the nominal load diffusion deviation of the model is less than 10%. Subsequently, the optimization results are validated through a three-dimensional finite element model, which yields a load diffusion deviation of less than 20%. Furthermore, an optimization model of a rigid frame representing stiffeners is developed. Comparative analyses between the two optimization models reveal that the load distribution results derived from the beam/plate model significantly outperform those of the rigid frame model, thereby underscoring the critical role of the skin structure in achieving load homogenization and diffusion.