An　effective　dispersion　process　to　cast　CNT-reinforced　in　a　concentrated　magnesium　alloy　(AZ31)　nanocomposite　was　investigated　in　this　study.　The　metal　magnesium　powder　was　first　coated　with　dispersed　CNTs　by　wet　process,　followed　by　the　fabricating　of　CNT/Mg　precursor　using　mechanical　briquetting　and　extrusion.　The　resultant　precursor　was　then　added　into　AZ31　alloy　during　the　melting　process.　Finally,　CNT/Mg　nanocomposites　with　grain　refinement　matrix　composite　were　fabricated　in　as-cast　and　as-extruded.　Compared　with　the　commercial　AZ31　alloy,　CNT/Mg　nanocomposites　exhibited　higher　yield　strength　of　270　MPa　with　an　increase　of　22.7%,　which　can　be　largely　ascribed　to　the　effective　dispersion　process　of　CNTs　in　the　alloy　matrix,　and　the　elongation　is　no　significant　decrease.　©　(2015)　Trans　Tech　Publications,　Switzerland.