A new energy absorption device composed of the foam aluminum and steel plate is introduced here, which can prevent the structure by attenuating the over pressure of air-shockwave produced by a gas blast effectively. In order to find out the blast wave pressure attenuation property of a cladding aluminum foam layer and an aluminum foam sandwich layer, the theoretical and numerical methods were used to study them through comparative analyses. Two kinds of typical structures are simulated numerically, which are the structure with one layer of a steel plate and the structure with both a layer of the steel plate and the device respectively. The results of the simulation show that the multilayer composite structure has the excellent capacity to reduce the blast loading and attenuate the over pressure of air-shockwave. the aluminum foam sandwich layer have the ability to attenuate the blast pressure before compressed to solid, and the ability decreases after the aluminum foam was completely compressed. The simulation experimental environment can be established and reference data can be provided for the design of a life-saving ball system by using numerical analysis methods.