An analytical study on the vibration isolation and energy absorption capability of closed-cell aluminum foams (Al-foams) is presented. A double degree of freedom (DDF) spring-damper-foam collision model(mimicking important equipment and/or personnel) is established to explore the physical mechanisms of shock attenuation when the system as a whole is dropped from a certain height and then collides with hard ground Compared with the classical solution of the single-degree of freedom (SDF) spring-damper model without foam protection, the impact loading of the DDF model can be significantly attenuated by the Al-foam. Moreover, the effects of key system parameters (such as spring stiffness, damping ratio, mass ratio, initial velocity and foam thickness) on optimal foam mass and minimum acceleration peak are discussed.