Breastmetastasisfromextra-mammarymalignancyisrare.Anincidenceof0.4%to1.3%hasbeenreportedinliterature.Theprimarymalignanciesthatmostcommonlymetastasizetothebreastareleukemia,lymphoma,andmalignantmelanoma.Inthisreport,twocasesofpulmonarymetastasistothebreastwerepresented.A40-year-oldfemalemanifestedarightbreastmassof2-monthduration.Afterphysicalexaminationwasperformed,apoorlydefinedmasswasnotedintheupperouterquadrantoftherightbreast.Another49-year-oldfemalemanifestedrightbreastmassof5-dayduration.Apoorlydefinedmasswasnotedinthelowerinnerquadrantoftherightbreast.Mammographyresultsalsorevealedbreastcancer.Thepatientsunderwentlocalexcision.Afterhistologicalandimmunohistochemicalanalyseswereconducted,aprimarylungcarcinomathatmetastasizedtothebreastwasdiagnosed.Anaccuratedifferentiationofmetastasistothebreastfromprimarybreastcancerisveryimportantbecausethetreatmentandprognosisofthetwodiffersignificantly.