A process for producing an L-amino acid from the corresponding DL- and/or L-amino acid amide represented by the general formula: ##STR1## wherein R is a substituted or unsubstituted alkyl group having one to 4 carbon atoms, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted aralkyl group, by action of an enzyme having hydrolytic activity to L-amino acid amides which is produced by Enterobacter cloacae or Pseudomonas sp.