A methodology has been developed to simplify the complex reaction mechanism for the methane and the ethane combustion processes. The methodology is based on the mass balances, the chemical kinetics, and equilibrium. To compare the results of the obtained reduced reaction system for methane, the Premix Mathematical Model from Sandia Laboratory was used. The temperature, composition, and velocity profiles of a methane-air mixture combustion flame were compared with the ones obtained from other mechanisms.