An aqueous organosilicon composition is prepared by mixing water with an organopolysiloxane having at least one ##STR1## group and having aliphatic radicals which are bonded to silicon via oxygen, a polyvinyl alcohol and/or a water-soluble cellulose ether containing hydroxyl groups in the presence of sufficient acid to provide a composition having an acid pH. The resultant composition may be neutralized and used as additives in aqueous paint compositions.