A recombinant plasmid pET-22b (+)-tao was successfully constructed by inserting the TAO oxidase gene derived from Pseudomonas to the plasmid vector pET-22b (+). The recombinant plasmid was transformed to the E. coli BL21 (DE3) to get E.coli BL21 (DE3)(tao). After recombinant the strain was cultured at 37 ℃ for 70-90 min, IPTG was added with a final concentration of 0.4 mmol/L. After induction for 6 h at 20 ℃, the TAO oxidase activity could reach 35 U/g. The concentration of heliotropin could reach 9.15 g/L after reaction at pH 8 and 30 ℃. Product was obtained in crystal after extraction by ethyl acetate and drying. IR and 1H-NMR verified that the crystal was heliotropin. HPLC showed that the purity was higher than 97%.