Mechanical properties of Al-Mg porous materials which were made by self melting reactions at low temperatures are investigated in this work. The results showed that the yield strength of Al-20%Mg was up to 240 MPa, and this is the compressive characteristics of brittle porous materials. The excellent of mechanical properties of Al-Mg porous material was analyzed and the reason was ascribed to the homogenous distributed pore with cell wall strengthening.