Abstract: The optimization of buckling-prone cylindrical hollow tubes and tubes with porous material cores is investigated. The load-carrying efficiency (the ratio of the critical load to the weight) and the buckling modes of cylindrical shells with porous cores subject to axial compression are studied. The parameters, such as the shell thickness and the relative density of porous core, which influence the structural load-carrying efficiency and the buckling modes, are optimized. A parametrical finite element modeling method and an optimization program written in PCL language of MSC/PATRAN are presented. The numerical results for the buckling analysis and optimization of a specific cylindrical shell structure show that increasing the shell thickness can improve the load-carrying capacity and the efficiency for thin-walled hollow shells, but the load-carrying efficiency may decrease when the thickness is increased to a threshold. Porous cores can increase the load-carrying capacity and efficiency greatly, and optimizing the shell thickness and relative density of the porous core can improve the load-carrying efficiency further.