The comparative study of the oxidative coupling of methane has been carried out over Bi2O3, 20 at.% Er/Bi2O3 and 0.2 at.% Li/Bi2O3 using O-2 and N2O as oxidants. It was shown that the rate of C-2 production was higher in the presence of N2O as compared with O-2 for undoped and Er doped Bi2O3 catalysts at the same level of methane conversion. For Li/Bi2O3 the rates of C-2 production were similar for both oxidants. Different mechanisms for N2O decomposition were suggested over doped and undoped Bi2O3.