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There are active oxygen species that contribute to oxidative coupling or the partial oxidation during the oxidative dehydrogenation of methane when using solid oxide catalysts, and those species have not been definitively identified. In the present study, we clarify which of the active oxygen species affect the oxidative dehydrogenation of methane by employing photo-catalysts such as TiO₂ or WO₃, which generate active oxygen from UV-LED irradiation conditions under an oxygen flow. These photo-catalysts were studied in combination with Sm₂O₃, which is a methane oxidation coupling catalyst. For this purpose, we constructed a reaction system that could directly irradiate UV-LED to a solid catalyst via a normal fixed-bed continuous-flow reactor operated at atmospheric pressure. Binary catalysts prepared from TiO₂ or WO₃ were either supported on or kneaded with Sm₂O₃ in the present study. UV-LED irradiation clearly improved the partial oxidation from methane to CO and/or slightly improved the oxidative coupling route from methane to ethylene when binary catalysts consisting of Sm₂O₃ and TiO₂ are used, while negligible UV-LED effects were detected when using Sm₂O₃ and WO₃. These results indicate that with UV-LED irradiation the active oxygen of O₂⁻ from TiO₂ certainly contributes to the activation of methane during the oxidative dehydrogenation of methane when using Sm₂O₃, while the active oxygen of H₂O₂ from WO₃ under the same conditions afforded only negligible effects on the activation of methane.