OBJECTIVE:To study the chemical constituents of the ethyl acetate extraction portion of Polygonum bistorta,pro-vide scientific basis for the basic research of its effective substances. METHODS:Taking the ethyl acetate extraction portion of P. bistorta 95％ ethanol extract,positive phase and reversed phase column chromatography were used for repeated isolation and purifi-cation,and the structures of the purified compounds were identified on the basis of physicochemical properties or spectral data. RE-SULTS:11 monomer compounds were isolated and identified as β-sitosterol(1),dihydromyricetin(2),quercetin(3),kaempferol (4),epicatechin(5),chlorogenic acid(6),rutin(7),gallic acid(8),1,2,3,4-tetrahydro-8-hydroxy-4-isopropyl-1-methylnaph-thalene-6-carboxylic acid (9),protocatechuic acid (10) and ellagic acid (11). CONCLUSIONS:The literature is confirmed that compound 2 is isolated from P. bistorta for the first time and compound 9 is isolated from Polygonum for the first time. The related research results have provided experimental references for further clarifying the effective substances of P. bistorta.