PurposeThe　purpose　of　this　paper　is　to　study　the　high　temperature　oxidation　behavior　of　Ti　and　C-added　FeCoCrNiMn　high　entropy　alloys　(HEAs).Design/methodology/approachCyclic　oxidation　method　was　used　to　obtain　the　oxidation　kinetic　profile　and　oxidation　rate.　The　microstructures　of　the　surface　and　cross　section　of　the　samples　after　oxidation　were　characterized　by　X-ray　diffraction　(XRD)　and　scanning　electron　microscope　(SEM).FindingsThe　results　show　that　the　microstructure　of　the　alloy　mainly　consisted　of　FCC　(Face-centered　Cubic　Structure)　main　phase　and　carbides　(M7C3,　M23C6　and　TiC).　With　the　increase　of　Ti　and　C　content,　the　microhardness,　strength　and　oxidation　resistance　of　the　alloy　were　effectively　improved.　After　oxidation　at　a　constant　temperature　of　800　degrees　C　for　100　h,　the　preferential　oxidation　of　chromium　in　the　chromium　carbide　determined　the　early　formation　of　dense　chromium　oxide　layers　compared　to　the　HEAs　substrate,　resulting　in　the　optimal　oxidation　resistance　of　the　TC30　alloy.Originality/valueMore　precipitated　CrC　can　preferentially　oxidize　and　rapidly　form　a　dense　Cr2O3　layer　early　in　the　oxidation,　which　will　slow　down　the　further　oxidation　of　the　alloy.