The invention relates to a method for producing biologically active β-NGF from the proform proNGF. After expressing the proform of the β-NGF in a prokaryotic host cell, the recombinant protein is isolated in the form of insoluble inactive aggregates (inclusion bodies). After the solubilization thereof in a strong denaturing agent and the subsequent conversion thereof into the natural conformation, which is determined by the disulfide bridges present in the natural β-NGF, biologically active β-NGF is obtained by subsequently splitting-off the prosequence.