In our continuing search for anti-oxidative compounds from oriental medicinal plants, Agrimonia pilosa was examined. Here we report the progress on the purification, biological activities and structural determination of a compound from Agrimonia pilosa. From the 100% methanol extract of Agrimonia pilosa, solvent partition fractions were prepared by using n-hexane(15-APH), chloroform(15-APC), butanol(15-APB) and water(15-APW). Among them 15-APB showed anti-oxidative activity. The 15-APB of Agrimonia pilosa showed 53% DPPH radical scavenging activity at 100 ppm. Using a series of ODS open column chromatographic purification steps, one compound, 15-APB-175 was purified. At 100 ppm, it showed anti-oxidative activity of 92.3%. The structure of 15-APB-175 was determined using ¹H and ¹³C NMR and MS spectroscopic methods and its structure was turned out to be a floavonol glucoside named (2S, 3S)-glucodistylin.