A procedure has been developed for the synthesis of oligopeptide amide using inverse substrates as acyl donors with amino acid amide instead of p‐nitroanilide as acyl acceptor and trypsins of different origin (bovine, Streptomyces griseusand chum salmon trypsins) as the catalyst. The effectiveness of this procedure was demonstrated by the synthesis of a pentapeptide, Boc‐[Leu5]‐enkephalin amide, as a model compound. The method was the first enzymatic method shown to be successful at each successive coupling step for the synthesis of the oligopeptide. Bovine and chum salmon trypsins were superior to Streptomyces griseustrypsin as the catalyst. Copyright © 2002 European Peptide Society and John Wiley & Sons, Ltd.