Amines are prepared by hydrogenation of the corresponding nitroaromatics in a vertical reactor whose length is greater than its diameter and which has in its upper region a downward-directed jet nozzle via which the reaction mixture and, if desired, part of the starting materials are introduced, has an outlet at any point on the reactor via which the reaction mixture is conveyed in an external circuit by means of a transport device back to the jet nozzle and has a flow reversal in its lower region, wherein at least part of the hydrogen and/or nitroaromatic starting materials used is fed into the liquid phase of the reactor in such a way that they travel upward in the liquid phase.