The invention provides a process for preparing SiOC-bonded polyorganosiloxanes by reacting, by processes known per se, hydroxyl-containing compounds with a stoichiometric excess of polyorganosiloxanes which contain —Si(H) units and are of the general formula (I) in the presence of one or more element compounds of main group III and/or of transition group 3 as a catalyst, wherein the reaction, on completion of conversion of the compounds containing hydroxyl groups, is continued until no further ≡Si—H groups are detectable by gas volumetric means, and also the compounds prepared in this way and their use.