For the investigation of medicinal resources the studies were carried out to evaluated the pharmaco-constituents in the Leaves of Parthenocissus tricuspidata(Vitaceae), of which leaves have been used in Korea as folk remedies for the treatments of arthritis, jaundice, toothache, neuralgia, and etc. From 1-butanol fraction of the MeOH extract, Compound I ($C_{21}H_{18}O_{13}$, Quercetin-3-O-$eta$-D-glucuronopyranoside), Compound II ($C_{21}H_{20}O_{12}$, Quercetin-3-O-$eta$-D-glucopyranoside) and Compound III ($C_{25}H_{28}O_{12}$, Quercetin-3-O-(6"-n-butyl)-$eta$-D-glucuronopyranoside) were isolated by column chromatographic separation using Sephadex LH-20 and ODS gel. Their structures were elucidated through instrumental analyses, such as $^{1}H$-NMR, $^{13}C$-NMR, IR, UV, El-Mass, FAB-Mass and GC. Especially compound III was Flavonol glycoside and named parthenosin.