The catalytic effect of NOx on methane oxidation in the absence of any olid catalyst has been investigated. The experimental results show that NOx has very good catalytic activity in the partial oxidation of methane. The predominant products for reactions in a CH4O2NOx co-feed mode are CO, CO2, H2O and H-2, CH3 OH, HCHO, and C2H4. Aromatics are also observed.