The enzymatic biotransformation of the monoterpenes R(+)-limonene, a-pinene and ?-terpinene was performed using chloroperoxidase from Caldariomyces fumago. The enzymatic reactions were carried out in acetonitrile:water mixtures and the obtained products were extracted with diethyl ether, dried with sodium sulphate and finally analyzed by gas chromatography- mass spectrometry (GCMS). Carvone and (E) -carveol were identified as biotransformation products of R(+)-limonene..