Magnetic　acoustic　emission　(MAE)　is　an　important　non-destructive　testing　method　commonly　used　to　evaluate　the　mechanical　properties　of　ferromagnetic　materials.　However,　there　are　few　reports　on　the　theory　or　numerical　models　of　MAE.　A　theoretical　MAE　model　considering　the　microstructure　(dislocation　density　and　grain　size)　is　proposed　in　this　paper.　The　influences　of　magnetization　parameters　and　microstructure　parameters　on　the　envelope　of　MAE　signal　are　analyzed　through　numerical　calculations.　After　that,　the　rationality　of　the　MAE　model　is　validated.　Based　on　the　MAE　predicted　signals　with　different　hardness　specimens,　the　dynamic　hysteresis　parameters　and　magnetized　structural　parameters　in　the　theoretical　model　were　inverted　with　the　genetic　algorithm.　The　results　demonstrate　that　the　MAE　signals　calculated　from　the　theoretical　model　under　the　inversion　parameters　are　in　good　agreement　with　the　experimental　signals,　and　the　maximum　error　between　the　inversion　values　of　the　key　hysteresis　parameters　and　the　theoretical　calculation　results　is　less　than　15%　.　Therefore,　the　theoretical　model　can　be　used　to　predict　the　MAE　signals.　©　2024　Science　Press.　All　rights　reserved.