A process is proposed for reprocessing the exhaust gas from a plant for producing hydroxylamine or hydroxylammonium salts by catalytic reduction of nitrogen monoxide with hydrogen for the purpose of utilization of at least a part of the nitrogen monoxide and if appropriate hydrogen present in the exhaust gas for producing hydroxylamine or hydroxylammonium salts, which comprises, in a first separation stage, selectively separating off nitrogen monoxide from the exhaust gas of the plant for producing hydroxylamine or hydroxylammonium salts.