Abstract: Based on tomographic images of closed-cell aluminum foams, a two-dimensional mesoscopic finite element (FE) model is created for idealized density-graded aluminum foams, with cell shape and geometric distribution accounted for. Numerical simulations are carried out to investigate the compressive deformation mechanisms, shock wave propagation and energy absorption capacity of the model density-graded foam under impact loading, with its average relative density and gradient coefficient fixed at 0.3 and 0.4, respectively. At relatively low impact velocity (10 m/s), the density-graded foam absorbs smaller total energy than its homogeneous counterpart. At sufficiently high impact velocities, however, the density-graded foam compressed along the negative gradient direction exhibits superior energy-absorbing performance. Such superiority is strengthened with increasing impact velocity.