The present invention is to provide a gene having asymmetric hydrolase activity which is useful for synthesis of an optically active carboxylic acid, its antipode ester, and lactone, and a hydroxycarboxylic ester asymmetric hydrolase enzyme (EnHCH) derived from Enterobacter sp. DS-S-75 strain (FERM BP-5494) which is bacteria belonging to the genus Enterobacter, a EnHCH gene shown by base sequence of SEQ. ID. NO: 1, a gene encoding a protein having an amino acid sequence of SEQ. ID. NO: 2, and E. coli DH5.alpha. (pKK-EnHCH) deposited to International Patent Organism Depositary, National Institute of Advanced Industrial Science and Technology as a deposition No. FERM BP-08466.