Abstract: The composite sandwich structure reinforced by metallic tubes is a novel type of ultra-light multifunctional structure. The calculation of the critical load took the influence of the transverse shear into account, and the transverse shear stiffness of the sandwich column was measured experimentally. The theoretical prediction of the critical load was validated by test. The buckling behavior of the composite sandwich column reinforced by metallic tubes was simulated using the finite element software ABAQUS, and the numerical result was well consistent with the theoretical prediction and experimental result. The relation between the critical load and the arrangement of metallic tubes was investigated numerically. The results show that the buckling mode of the composite sandwich column reinforced by metallic tubes is dominated by transverse shear buckling; the critical load increases with the decrease of the spacing of tubes along the longitudinal direction; keeping the height and total mass of tubes fixed, decreasing the radius and the spacing of metallic tubes can increase the critical load. The results are valuable for the design of the sandwich column reinforced by metallic tubes under longitudinal compressive load.