To　obtain　excellent　mechanical　properties,　Al-Mg　alloy　was　processed　through　a　combination　of　equal　channel　angular　pressing　(ECAP)　and　micro-alloying　techniques.　In　this　study,　the　microstructural　evolution　of　Al-Mg-ErZr　alloy　during　ECAP　at　room　temperature　were　systematically　investigated.　TEM　results　confirm　that　the　Al3(Er,　Zr)　particle　exists　in　the　initial　material　and　saturated　dislocations　form　dense　dislocation　walls.　The　grains　were　refined　with　an　average　grain　size　of　2.8　mu　m　after　4　passes　of　ECAP.　Continuous　dynamic　recrystallization　was　identified　and　this　mechanism　led　to　the　formation　of　fine　grain　structure.　The　(101)-oriented　coarse　grains　were　relatively　stable　once　they　had　been　formed.