The present invention relates to a novel method for the preparation of 1,4-diaminobutane [DAB]. The method according to the present invention involves at least one biocatalytic step which comprises the biocatalytic production of at least one N-protected precursor of DAB. The present invention also relates to a method for the preparation of DAB involving at least one biocatalytic step, and comprising the steps of a) biocatalytically preparing an N-protected precursor of DAB yielding a—biocatalytic reaction mixture containing the N-protected precursor of DAB, b) recovering the N-protected precursor from the biocatalytic reaction mixture and c) converting the N-protected precursor into DAB. More in particular, the present invention relates to a method for the preparation of DAB, wherein the at least N-protected precursor of DAB is selected from the group consisting of N5-protected ornithine, N-protected DAB, and N-protected 4-aminobutyraldehyde.