Microwave enhanced combustion of methane-air mixture in a ceramic burner is studied and the results suggest perturbation of the assumed Boltzmann distribution of molecular energy levels. A small signal gain, which represents the level of amplification of an incident beam in a medium, was detected using a CO, laser. An increase in the signal ratio of two MCT photodetectors when the combustion zone was irradiated by microwaves (2.45 GHz) indicates amplification of infrared radiation (10.6 mum), hence the possibility of using the system for laser applications. However, statistical analysis reveals that varying levels of microwave power are not significantly different.