Microwave　ablation,　as　an　emerging　method　for　treating　lung　cancer,　has　been　widely　used　because　of　its　advantages,　such　as　being　less　invasive　and　having　fewer　side　effects　compared　with　other　therapies,　such　as　surgery　and　chemotherapy.　The　key　to　microwave　ablation　is　to　destroy　the　tumor　tissue　while　minimizing　the　damage　caused　to　the　surrounding　healthy　tissues.　Based　on　the　heat　transfer　model　of　porous　media,　a　two-dimensional　simulation　model　of　a　spherical　tumor　surrounded　by　healthy　tissue　is　established　in　this　paper.　The　effects　of　tumor　diameter,　tumor　porosity,　and　microwave　ablation　power　on　the　highest　temperature,　ablation　area,　and　volume　of　the　tumor　tissue　were　studied　by　using　the　software　COMOSL　Multiphysics.　The　results　show　that　the　porous　heat　transfer　model　is　more　practical　than　the　Pennes　biological　heat　transfer　model.　The　tumor　diameter　and　the　tumor　porosity　have　a　great　influence　on　the　maximum　temperature,　the　ablation　area　and　volume.　In　this　study,　a　more　realistic　model　of　microwave　ablation　of　lung　tumors　was　established,　and　the　ablation　results　were　predicted　accurately,　which　provided　the　basic　reference　data　for　the　selection　of　clinical　therapeutic　parameters　of　microwave　ablation　of　lung　tumors.　To　a　certain　extent,　it　can　ensure　that　the　ablation　area　completely　covers　the　tumor　and　reduces　the　risk　of　tumor　recurrence,　which　is　of　great　significance　in　the　accurate　treatment　of　pulmonary　tumors　by　microwave　ablation.