The present invention relates to a process for the coammoximation, that is to say for the simultaneous ammoximation, of ketones, in particular of cyclic ketones such as cyclododecanone and cyclohexanone. Ammoximation is taken to mean here the preparation of oximes from ketones or aldehydes together with hydrogen peroxide and ammonia and in the presence of a catalyst which essentially consists of silicon, titanium and oxygen, for example titanium silicalite.