There is disclosed the preparation and recovery of proteins, in particular of enzymes, by controlled proteolytic cleavage of pro-proteins, in particular pro-enzymes, in a single method step, wherein a pro-protein-containing solution is contacted with a protease and with a solid carrier which has a higher affinity to the protein than to the pro-protein or to the functionally inactive degradation products thereof, the pro-protein being proteolytically cleaved to said protein, and the protein being selectively separated by absorption on the solid carrier.