Abstract: A process for the enzyme-catalyzed preparation of prepolymers for the production of plastics, based on an enzyme-catalyzed polymerization of monomer or oligomer compounds in a single phase aqueous solution, as well as the separation of the prepolymers precipitated therefrom and their subsequent use for the production of plastics and plastic articles obtainable therefrom. In particular, the invention relates to respective methods for enzyme-catalyzed preparation of prepolymers with polyamide-type bonding structure for the production of polyamide-based plastics.