Abstract: A combustion system with low pollutant emission, of the pre-mixing type for gas turbines, in which the combustion air passes from the interspace to the pre-mixing chamber via apertures in this latter, their degree of opening being varied, in accordance with the fuel quantity used, by corresponding apertures in a rotatable drum, and in which a series of small holes fed with additional fuel is provided in the interspace. Further flame stabilization expedients and differential cooling of the combustion chamber are also provided.