This study proposes a multilayer strategy combined with topology optimization to design ultrastiff lattice metamaterials. The multilayer strategy expands the design space and increases design freedom, while topology optimization explores the design space to achieve optimal performance. The optimized lattice structures combine beam, plate, and shell elements, achieving ultrahigh stiffness and improved energy absorption under large deformation. The multilayer strategy also enables tunable dimensions, such as shape, thickness, and layer configuration, allowing for desired mechanical properties like isotropic elasticity and functionally graded stiffness. The study demonstrates that the multilayer strategy and topology optimization can be applied to various engineering fields, including acoustic, electrostatic, and fluid field tuning. The results show that the optimized lattice structures exhibit superior mechanical performance, with the Opt-P-4 lattice reaching the Voigt upper bound for anisotropic materials. Physical experiments validate the numerical simulations, showing that the optimized lattices have significantly improved stiffness and energy absorption capabilities. The study also highlights the importance of considering boundary conditions and the impact of material properties on the performance of the lattice structures. The multilayer strategy and topology optimization provide a flexible and efficient method for designing lattice metamaterials with tailored properties for various applications.This study proposes a multilayer strategy combined with topology optimization to design ultrastiff lattice metamaterials. The multilayer strategy expands the design space and increases design freedom, while topology optimization explores the design space to achieve optimal performance. The optimized lattice structures combine beam, plate, and shell elements, achieving ultrahigh stiffness and improved energy absorption under large deformation. The multilayer strategy also enables tunable dimensions, such as shape, thickness, and layer configuration, allowing for desired mechanical properties like isotropic elasticity and functionally graded stiffness. The study demonstrates that the multilayer strategy and topology optimization can be applied to various engineering fields, including acoustic, electrostatic, and fluid field tuning. The results show that the optimized lattice structures exhibit superior mechanical performance, with the Opt-P-4 lattice reaching the Voigt upper bound for anisotropic materials. Physical experiments validate the numerical simulations, showing that the optimized lattices have significantly improved stiffness and energy absorption capabilities. The study also highlights the importance of considering boundary conditions and the impact of material properties on the performance of the lattice structures. The multilayer strategy and topology optimization provide a flexible and efficient method for designing lattice metamaterials with tailored properties for various applications.