Eight known compounds were isolated from the whole plants ofArenaria serpyllifolia L. by solvent fractionation and subsequent separations with silica gel, ODS, Sephadex LH-20 and semi-preparative HPLC chromatography. Their structures were determined by spectroscopic analysis and identified as quercetin （1）, quercetin 7-O-α-L-rhamnoside （2）, quercetin 3-O-α-L- rhamnoside （3）, 3-O-methyl quercetin （4）, 1,5-dihydroxyxanthone （5）, 1,5-dihydroxyxanthone-6-O-β-D-glucoside （6）, 5-hydroxy- l-methoxyxanthone （7） and 6-deoxyisojacareubin （8）. All these compounds were isolated from this title plant for the first time, and compounds 5-8 were obtained from genus Arenaria for the first time.
