The extract of Ginkgo biloba leaves was measured for inhibitory activity against xanthine oxidase. Aceton extract of G. biloba leaves showed strong inhibitory activity. Inhibitory activities of the fractionated extract were in the order of water > ethyl acetate fractions. Two fractions exhibiting strong inhibitory activities ware further purified via repeated silica gel, Amberlite IRN-78, Polyclar AT, and Sephadex LH-20 column chromatographies. Active components were isolated and identified through $^1$H-NMR and $^{13}$ C-NMR. The compounds were characterized as kaempferol 3-Ο-$alpha$-(6$^{"′}$-p-coumaroylglucosyl-$eta$-1,4-rhamnoside), and quercertin 3-Ο-$alpha$-(6$^{′}$-p-coumaroylglucosyl-$eta$-1,4-rhamnoside).