Abstract: Al and Al alloy foam with spherical pores were prepared by foaming in melt,and tensile experiment was carried out to study the effect of porosity on the tensile properties.The results show that the tensile stress-strain curves of spherical pore Al foam were similar to that of spherical pore Al alloy foam.They all showed four stages of linear elastic deformation,platform,plastic increase and failure.Compared with the compressive properties of spherical pore Al and Al alloy foam,the tensile strength was far less than the compressive strength.The tensile strength decreased with the increasing porosity.