Abstract: To explore the influence of steel and GFRP structural configuration on the perforation-resis-tance of a composite armor system of warship bulkhead, a series of high velocity ballistic impact experi-ments are performed.The outer and inner composite armor systems of warship bulkhead are simulated us-ing homogeneous steel plates prefaced and backed with composite laminates, respectively. Failure modes and energy absorption for the two types of combined targets are analyzed and compared with each other. Based on the experimental results, the compounded structure subjected to the impact caused by cube pro-jectiles is simulated using finite element program ANSYS/LS-DYNA, where the process of penetration is investigated and compared with experiment results. It is observed that the numerical results are in good agreement with the experimental results; the failure modes for the composite armors in the two types of com-bined targets are mainly the shear punch failure of steel plates and the fiber shear fracture of GFRP, while the GFRP in the combined target consisted of front steel plates and composite backed armors also has ten-sile failure of fibers; the combined target consisted of front steel plates and composite backed armors ab-sorbs much more energy than that consisted of front composite armors and steel backed plates.