Using ginseng (Panax ginseng C. A. Mey.) hairy roots as a bioreactor, exogenous hydroquinone (HQ) was added aseptically to suspension of hairy roots on 22 d. Twenty-four hours after the addition of HQ, the hairy roots were separated from the medium. Through identification of TLC and HPLC, it was proved that hydroquinone has been bioconversed into arbutin, and arbutin from hairy root of P. ginseng was isolated and identified.