<p>Metallic lattice structures represent advanced architected materials delivering exceptional properties with promising lightweight potential. With the rapid advancement of additive manufacturing, these structures have garnered increasing research interest. However, most metallic lattice structures generally exhibit anisotropic characteristics, which limits their application ranges. Additionally, a limited number of studies have successfully developed precise mechanical models, which have undergone experimental validation, for the purpose of describing the mechanical response exhibited by additively manufactured metallic lattice structures. In this study, Kelvin lattice structures with varying porosities were systematically designed and fabricated using laser powder bed fusion (LPBF) technology. By integrating finite element simulations with experimental characterization, an enhanced mechanical model was developed through a modification of the Gibson-Ashby model, providing an accurate quantitative description of the relationship between porosity and mechanical properties. The results show that the revised mechanical model can accurately describe the relationship between the geometric parameters and properties of metallic lattice structures. Specifically, the designed Kelvin lattice structures exhibit a smooth stress-strain curve with an obvious yield platform, demonstrating isotropic mechanical properties in all the three spatial directions. This enhances their suitability for complex loading conditions. Meanwhile, the microstructure and manufacturing accuracy of the Kelvin lattice structures were observed and analyzed by micro computed tomography. The results show that the fabricated metallic lattice structures achieved precise dimensional control and optimal densification. This study presents the complete process involved in modeling the Kelvin structure, including its conceptualization, manufacturing, implementation, and ultimately, disposal.</p>