The product distributions for partial oxidation of methane on Fe2(MoO4)3 catalyst were changed remarkably when the oxidant was switched from oxygen to nitrous oxide. When oxygen was used as the oxidant, the main products were HCHO and CO. However, when nitrous oxide was used, the formation of HCHO was greatly suppressed and C2 hydrocarbons (C2H6 and C2H4) were newly produced. The difference in kinetic behaviors between the two reactions using nitrous oxide and oxygen as the oxidant can be explained in terms of the competitive conversions of methyl intermediate into HCHO and C2H6. In the case of nitrous oxide as the oxidant, the adsorbed methyl intermediate would be transformed predominantly into C2H6 due to a low steady-state concentration of the active oxygen species on Fe2(MoO4)3.