PURPOSE: To obtain glutarylaminodeacetylcephalosporanic acid useful as a synthetic raw material for cephalosporin antibiotics or the like easily efficiently in high yield by making deacetylcephalosporin C contact with catalase and D-amino acid oxidase.

CONSTITUTION: This 7-glutarylaminodeacetylcephalosporanic acid is obtained by making deacetylcephalosporin C contact with catalase and D-amino acid oxidase. Further, 7-aminodeacetylcephalosporanic acid is preferably produced by making 7-glutarylaminodeacetylcephalosporanic acid contact with a deacylating enzyme derived from a bacterium of the genus Acinetobacter.