Considering　the　severe　oxide　skin　exfoliation　in　supercritical　boilers,　this　paper　conducted　the　research　on　the　corrosion　behavior　of　heat-resistant　steel　in　supercritical　carbon　oxygen　system.　The　high-temperature　corrosion　behaviors　of　heat-resistant　steels　T91,　TP347HFG　and　Sanicro　25　at　650　and　15　MPa　for　500　h　in　supercritical　carbon　dioxide　environment　were　studied.　To　acquire　the　corrosion　behavior　data　of　investigated　heat-resistant　steel,　the　Raman　analysis,　X-ray　diffraction　and　glow-discharge　optical　emission　spectrometry　were　employed　to　characterize　the　corrosion　products.　The　mass　change　of　the　heat-resistant　steels　was　obtained　by　the　analytical　balance　result.　Weight　gain　results　showed　that　the　corrosion　kinetics　of　the　investigated　heat-resistant　steels　obey　a　parabolic　corrosion　law.　The　corrosion　products　formed　on　T91　are　mainly　composed　of　Fe3O4,　(Fe,Cr)3O4　and　carbides　mixed　in　the　substrate　from　the　gas/oxide　interface　to　the　substrate.　Corrosion　products　formed　on　austenite　heat-resistant　steel　were　mainly　Cr2O3,　Mn　and　Si　oxides　and　carbides　in　the　substrate.　Moreover,　some　carbon　was　detected　on　the　surface　of　corrosion　products.　Based　on　the　above　corrosion　products,　the　corrosion　degradation　depth　was　used　to　evaluate　the　corrosion　resistance　of　steels　in　high-temperature　supercritical　carbon　dioxide.　The　corrosion　degradation　depths　of　the　three　steels　were　in　the　following　order:　Sanicro　25＞TP347HFG＞T91.　©　2019,　Editorial　Office　of　Journal　of　Xi＇an　Jiaotong　University.　All　right　reserved.