Abstract: Aimed at investigating the relation between the liner materials and flight characteristics of explosively formed projectile (EFP) in water, we studied underwater penetration capacities of EFP, which are formed by three groups of materials, namely, different density materials (10 steel, tantalum and aluminum), same density materials (pure iron, 10 steel, 20 steel), and high-density materials (tantalum and tungsten), using ANSYS/LS-DYNA software and on the basis of experimental data of copper material EFP in water. In addition, the effects of liner material on velocity decrease of EFP was presented. The results show that density plays a crucial role on the penetration capacity of EFP in water. Given the shape of EFP, the ability of keeping velocity are improved with increasing density. Correspondingly, the tendency of velocity reduction is similar for EFP with same density. Tantalum, tungsten, and other high-density metal material liners have broad prospects in the application of underwater shaped charge warhead.