Based　on　the　photovoltaic　characteristics　of　GeSn-based　materials　and　the　theory　of　stacked　solar　cells,　Ga0.47In0.53As/Ge0.79Sn0.21　dual-junction　thermophotovoltaic　cell　has　been　simulated　and　studied　for　the　first　time.　According　to　existing　experimental　material　parameters,　the　structure　of　the　cell　is　optimized,　and　the　photoelectric　performance　of　the　cell　is　profoundly　studied.　The　findings　indicate　that　the　doping　concentrations　of　the　top/bottom　cell　are　N-a(d),N-t/N-a(d),N-b　=　50(7)　x　10(16)/17(2)　x　10(19)　cm(-3),　which　exhibits　superior　photoelectric　conversion　performance.　For　reducing　material　consumption　and　achieving　high　performance,　the　thickness　of　the　emitter　(base)　of　the　top/bottom　cell　can　be　selected　as　0.8　similar　to　2.0(2.0　similar　to　4.0)/0　similar　to　0.2(1.0　similar　to　4.0)　mu　m　(T-BB　=　1500　K).　With　radiator　temperatures　increasing,　the　conversion　efficiency　of　the　cell　significantly　improves,　and　the　open　circuit　voltage　of　the　cell　can　reach　0.70　similar　to　0.91　V　(1000　similar　to　2000　K).　The　research　results　can　guide　the　design　and　fabrication　of　high-efficiency　and　economical　GeSn-based　multi-junction　thermophotovoltaic　cells,　and　can　also　provide　a　new　research　and　development　direction　for　low-cost　thermophotovoltaic　cells.