The behavior of lattice oxygen species of the ferroelectric material during methane oxidation was investigated using a nonthermal plasma reactor packed with BaTiO 3 pellets. Lattice oxygen species in BaTiO 3 play an important role in the formation of N 2 O and the oxidation of CH 4 . The oxidation products such as CO and CO 2 were formed from independent reaction pathways. Lattice oxygen species were able to preferentially oxidize the carbon species deposited on the pellet surface into CO. Also, N 2 O and NO x were independently formed in the N 2–O 2 reaction, suggesting that different oxygen species give N 2 O and NO x. N 2 O was produced by the oxidation of molecular nitrogen with lattice oxygen species.