Inthisarticle,anovelheattreatmentmethod,deformationheat(DH)treatment(extrusion+aging),wasemployedonahypereutecticaluminumsiliconalloy(LM28-0.3wt.%Nd),anditseffectonmicrostructureandmechanicalpropertiesofthisalloywasinvestigated.ItcanbeconcludedthattheeutecticmicrostructuredisappearsaftertheDHtreatment,inthemeantimethemorphologyofα(Al)solidsolutionwastransformedfromfir-treeandcellulartoequiaxed,Siwasrefinedwithgrainsizesofabout1-10μmanddistributeddispersedly,evensomeofthembecameglobularshape,whichcanreducestressaccumulationeffectively.MechanicalpropertiestestindicatedthattheDHtreatmentcouldsignificantlyimprovetheroom-temperaturestrengthandhavelittleeffectonthehigh-temperaturestrengthofLM28-0.3wt.%Ndalloy.Thefracturemechanismisductilefracturebyfracturemorphologyanalysis.