Abstract: To investigate the antibacterial activities and chemical constituents of Polygonum aviculare L.Silica gel and Sephadex LH-20 column chromatography was applied for isolation of the constituents and their structures were identified by means of spectroscopic and chemical data.The antibacterial experiments were studied on 5 tested strains in vitro,which showed that the ethyl acetate extraction of it had a certain antibacterial activities against tested strains.Ten compounds (1-10) were isolated and their structures were identified as following:methyl gallate(1),β-daucosterol(2),kaempferol(3),quercetin(4),gallic acid(5),avicularin(6),quercitrin(7), myricetin-3-O-(3′′-O-galloyl)-rhamnopyranoside (8),myricitrin(9) and juglanin(10).Compounds 1 and 8 are isolated from this plant for the first time.Compound 8 is isolated from the plants of Polygonaceae for the first time.

Key words: Polygonum aviculare L., Polygonaceae, methyl gallate, myricetin-3-O-(3&prime, &prime, -O-galloyl)-rhamnopyranoside