Multi-component　solid　solutions　with　non-stoichiometric　compositions　are　characteristics　of　ultra-high　temperature　carbides　as　promising　materials　for　hypersonic　vehicles.However,for　groupⅣ　transition-metal　carbides,the　oxidation　behavior　of　multi-component　non-stoichiometric(Zr,Hf,Ti)Cx　carbide　solid　solution　has　not　been　clarified　yet.The　present　work　fabricated　four　kinds　of　(Zr,Hf,Ti)Cx　carbide　solid　solution　powders　by　free-pressureless　spark　plasma　sintering　to　investigate　the　oxidation　behavior　of　(Zr,Hf,Ti)Cx　in　air.The　effects　of　metallic　atom　composition　on　oxidation　resistance　were　examined.The　results　indicate　that　the　oxidation　kinetics　of　(Zr,Hf,Ti)Cx　are　composition　dependent.A　high　Hf　content　in　(Zr,Hf,Ti)Cx　was　beneficial　to　form　an　amorphous　Zr-Hf-Ti-C-O　oxycarbide　layer　as　an　oxygen　barrier　to　enhance　the　initial　oxidation　resistance.Meanwhile,an　equiatomic　ratio　of　metallic　atoms　reduced　the　growth　rate　of　(Zr,Hf,Ti)O2　oxide,increasing　its　phase　stability　at　high　temperatures,which　improved　the　oxidation　activation　energy　of(Zr,Hf,Ti)Cx.