Abstract: In this paper the radiolysis of the aqueous solution of 1, 8-dihydroxy anthra-quinone glucoside has been investigated, the results are as follows.1.OH radical reacted with 1,8-dihydroxy anthraquinone-β-D-glucocide leading to the radiolysis of glucoside but no glucosidic bond rupture was found.2.Two radiolysis products have been obtained. Product may be an aliphatic alcohol which comes from the decomposition of glucose radical. ProductⅡ is still a glucoside which may be a trihydroxy anthraquinone glucoside.3.Using competition kinetics we have got k_{OH·+glucosidc}=2.9×10⁹mol^-1s^-1.