A novel epoxide hydrolase from Aspergillus niger SQ-6 has now been cloned by inverse PCR. Its gene shows eight exons including a non-coding exon at its 5′-terminal (GenBank Accession No. AY966486). Phylogenetic analysis using deduced amino acid sequence (395 aa) confirms it as an epoxide hydrolase and shares 58.3% identity with that of A. niger LCP521 (GenBank Accession No. AF238460). The predicted catalytic triad is composed of Asp 191 , His 369 and Glu 343 . Active recombinant epoxide hydrolase has been successfully expressed in Escherichia coli as protein fusions with a poly-His tail. Scale-up fermentation can yield 2.5g/L of recombinant protein. The electrophoretic pure recombinant protein, which shows similar characterization as natural enzyme purified from A. niger SQ-6, can be easily purified by Ni 2+ -chelated affinity and gel-filtration chromatography. Optimal pH and temperature for purified enzyme are pH 7.5 and 37°C, respectively. The K m , k cat and maximal velocity (V max ) for p-nitrostyrene oxide are determined to be 1.02mM, 172s −1 and 231μmol min −1 mg −1 , respectively. The enzyme can be inhibited by oxidant (H 2 O 2 ), solvent (Tetrahydrofuran) and several metal ions including Hg 2+ , Fe 2+ and Co 2+ . This (R)-stereospecific epoxide hydrolase exhibits high enantioselectivity (enantiomeric excess value, 99%) for the less hindered carbon atom of epoxide. It may be an industrial biocatalyst for the preparation of enantiopure epoxides or vicinal diols.