One　of　the　important　research　fields　in　tumor　nanomedicine　is　the　novel　tumor　physical　therapy　strategy　called　magnetic　induction　hyperthermia.　It　was　developed　through　the　following　views:　Tumor　cells　have　worse　thermal　tolerance　than　normal　cells,　and　magnetic　iron　oxide　nanoparticles　can　generate　heat　under　the　action　of　an　alternating　magnetic　field　(AMF).　According　to　its　principle,　magnetic　nanoparticles　serve　as　a　thermal　medium　under　AMF　for　locating　tumors　and　absorb　the　energy　of　the　external　magnetic　field　to　generate　heat　through　several　factors,　including　hysteresis　loss　and　relaxation　loss;　consequently,　the　tumor　tissue　locally　heats　up　rapidly,　causing　tumor　cell　apoptosis.　Compared　with　the　traditional　tumor　hyperthermia　therapy,　magnetic　induction　hyperthermia　has　no　limitation　on　penetration　depth,　has　no　drug　resistance　in　physical　therapy,　causes　minimal　side　effects　of　iron　oxide　nanoparticles,　and　is　applicable　in　clinical　tumor　treatment.　However,　the　application　of　tumor　magnetic　hyperthermia　still　have　several　bottlenecks,　including　the　following:　(1)　The　biological　effects　and　mechanisms　of　magnetic　induction　heating　remain　poorly　understood;　(2)　the　current　iron　oxide　hyperthermia　agent　has　low　magnetothermal　conversion　efficiency;　(3)　nano-targeted　delivery　efficiency　is　low　and　cannot　achieve　precise　targeted　magnetic　hyperthermia;　(4)　the　equipment　generating　a　magnetic　field　is　limited.　Nonetheless,　with　the　rapid　advancement　of　nanomaterial　synthesis　technology　and　the　in-depth　understanding　of　the　biological　effects　of　magnetic　nanomaterials,　research　on　magnetic　nanomaterials,　especially　iron　oxide,　has　greatly　improved　the　application　of　tumor　magnetic　hyperthermia　as　a　new　and　smart　strategy.　Its　application　can　mediate　external　fields.　For　instance,　optimizing　the　size,　morphology,　composition,　and　surface　modification　of　magnetic　nanoparticles　is　necessary　to　improve　magnetic　hyperthermia　performance.　This　study　aimed　to　improve　the　curative　effect　of　magnetothermal　activity　on　tumors,　further　understand　the　heat　generation　mechanism　of　magnetic　nanomaterials,　optimize　the　conversion　efficiency　of　thermotherapy　agents,　and　enhance　the　tumor-targeting　of　magnetic　nanoagents　and　magnetic　field　generating　equipment.　Herein,　we　review　the　latest　research　progress　of　magnetic　nanomaterials　in　tumor　magnetic　hyperthermia　and　discuss　the　prospects　for　tumor　magnetic　hyperthermia　research.　The　nanosized　magnetic　iron　oxide　served　as　a　heat　source.　Although　the　nanoparticle　concentration　at　the　tumor　cells　does　not　produce　macroscopic　heating,　magnetic　nanoparticles　can　induce　tumor　cell　apoptosis　under　AMF.　The　local　heat　shows　steep　exponential　decays　with　an　increasing　distance　from　the　nanoparticle　surface.　Thus,　nanoscale　magnetic　heating　may　exert　biological　effects　on　tumor　cells　by　regulating　the　interaction　network　of　biological　macromolecules　(such　as　proteins,　nucleic　acids,　and　polysaccharides)　and　enzyme　catalytic　activity　or　changing　the　tumor　microenvironment.　Further　investigation　is　required　to　explore　the　biological　effects　and　mechanisms　of　nanoscale　magnetic　induction　heating,　design　safe　and　efficient　smart　nanopreparations,　develop　new-generation　magnetic　hyperthermia　equipment,　and　comprehensively　apply　nanotechnology　methods　and　nanoscience　principles　to　tumor　magnetic　hyperthermia.　To　elucidate　the　mechanism　of　nanoscale　magnetothermal　effect　on　life　activities,　we　need　to　establish　a　new,　accurate,　safe,　and　efficient　magnetic　nanoparticle　hyperthermia,　which　will　build　a　solid　foundation　for　the　diagnosis　and　treatment　of　diseases　using　magnetic　nanomaterials　in　the　future.　©　2021,　Science　Press.　All　right　reserved.