Abstract: Mechanical alloying powders were prepared by blending the mixture of pure Al powder and Al-Mg alloy powder with carbon or organic agents （e.g. methanol, stearic acid,etc.）in a high energy ball milling machine. The powder Mixture was compacted into bars by cold isostatical pressing equipment. The compact bars were extruded at 820°K with a reduction ratio of 26:1. The mechanical properties of the dispersion-strengthening Al-Mg alloys made by above process technique were super: as an example of No. 54 alloy, σ_b 519-529 MN/m², σ_0.2 510-519 MN/m², δ4-6%, ψ9-14%. The experimental results have also indicated that these alloys can be compared with those of conventional casting Al-Mg alloys. The mechanical properties of studied Al-Mg alloys has been remarkably improved. After annealing at 573°k for 100 hours, there was a little decrease even no decrease in the ultimate tensile strength of the alloy. Therefore, these alloys have a potential to be used as a kind of structural materials.