The present invention provides a novel esterase derived from Ideonella sp. 0-0013 strain (FERM BP-08660) having the following properties: (1) function, substrate specificity: hydrolyzes methyl 3-hydroxypalmitate to generate 3-hydroxypalmitic acid and methanol; (2) optimal temperature for functioning: 37.degree. C.; (3) optimal pH and stable pH range: pH 7 or more to pH 10 or less; (4) temperature stability: 97% of the enzyme is stable at 43.degree. C.; (5) inhibition, activation, and stabilization: activated by sodium ion and potassium ion, and inhibited by strontium ion, iron ion (divalent), and methyl palmitate; (6) molecular weight: about 46,500 Da (by SDS-PAGE), about 41,000 Da (by a gel filtration method); and (7) isoelectric point: pI 4 (by polyacrylamide gel isoelectric focusing method); a microorganism producing the enzyme; and a method of producing the enzyme.