A process for decomposing organohalogen compounds which are present in dust-laden gases which have a carbon content of less than 0.6% by weight, by oxidative breakdown with the aid of solid catalysts suitable for this purpose, whereina) the dust is deposited from the gases at 250.degree.-500.degree. C., and the dust-free gas is passed together with oxygen or an oxygen-containing gas over the catalyst, orb) the deposition of the dust takes place at below 250.degree. C., the organohalogen compounds are desorbed from the dust in an oxygen-containing gas stream at 250.degree.-500.degree. C., and the gas stream is passed over the catalyst, orc) the dust-laden gas is passed in the presence of oxygen over the catalyst at 250.degree.-500.degree. C., and the dust is subsequently removed.