A protease having the following characteristics: (i) a molecular weight of 21,000.+-.1,000 (by SDS-PAGE) and (ii) specific protease activity cutting the Gly-Phe site of a peptide or protein comprising amino acid sequence (1) below, cutting the Gly-Phe site of a peptide or protein comprising amino acid sequence (2) below, or cutting the Ser-Leu site of a peptide or protein comprising amino acid sequence (3) below: TABLE-US-00001 (1) (SEQ ID NO:4) Pro-Gln-Gly-Phe-Gln-Gly-Pro (2) (SEQ ID NO:5) Pro-Ala-Gly-Phe-Ala-Gly-Pro (3) (SEQ ID NO:6) Gln-Thr-Gln-Ser-Leu-Val-Thr-Pro. DNA encoding this protease, including vectors containing this DNA, and a method for producing this protease by transforming a cell with this DNA.