Abstract: This invention relates to a burner with low emission of polluting gases, comprising, in a conduit, an injector of fluid fuel which creates in the conduit, supplied with combustion-supporting air heated in an exchanger, a fuel/air mixture. The latter burns, creating a flame which clings to a stabilizer constituted for example by a hollow piece, of V-section, obturating a central part of the cross-section of the conduit. Downstream of this stabilizer there is placed an obstacle causing a local reduction follwed by a sudden increase in the cross-section of the conduit in order to promote oxidation of the carbon monoxide.