Objective To study the chemical constituents of the 95% EtOH extract of the rhizoma of Polygonum bistorta L.Methods The chemical constituents were isolated by column chromatography and identified by physico-chemical characters and spectroscopic analysis.Result Five compounds were isolated,and identified as gallic acid (Ⅰ),succinic acid (Ⅱ),quercetin (Ⅲ),quercetin-5-O-β-D-glucopyranoside (Ⅳ) and 3,4-dihydroxy benzoic acid (Ⅴ).Conclusion CompoundⅡ,Ⅳ were isolated from Polygonum genus for the first time.