L-phenylalanine-p-nitroanilidase (PPA-ase) from vetch cotyledons was purified 1600-fold with a 6.7% recovery. Data from gel electrophoresis suggest that the preparation obtained (specific activity 232 U/mg) contains only a small admixture of inactive protein. PPA-ase splits off more than 14% of peptide bonds of di- and oligopeptides formed by reserve protein hydrolysis with endogenous protease A. The cotyledon PPA-ase is located outside the protein bodies and differs from seedling enzymes hydrolyzing PPA by its chromatographic behaviour. The results obtained suggest that PPA-ase takes part in the hydrolysis of short peptides produced during the reserve protein degradation and transported from protein bodies in the cytoplasm.