Objective: To study the chemical constituents of Polygonum multiflorum leaves and lay a foundation for the research and development of functional food of P. multiflorum. Methods: Organic solvent fractions was performed on the alcohol extract of P. multiflorum leaves to obtain different fractions parts such as petroleum ether， dichloromethane， ethyl acetate， n-butanol， and water. Anti-inflammatory activities were carried out on different extraction parts. The fractions with strong anti-inflammatory activity were separated and purified by using silica gel and C18 column combined with semipreparative HPLC methods. Results: The ethyl acetate fraction had no cytotoxicity on RAW264.7 cells in the concentration range of 0-100 μg/mL and showed dose-dependent inhibition of NO production. Petroleum ether and dichloromethane fractions displayed no cytotoxicity in the concentration range of 0-25 μg/mL， the inhibitory rate on NO of dichloromethane fraction (51.47%) was higher than the fraction of petroleum ether (43.91%). Eleven compounds were isolated from the fractions of ethyl acetate and dichloromethane. The chemical structures were identified as 2，3，4，6-tetrahy-droxyacetophenone-3-O-β-D-glucoside (1)， myricitrin (2)， quercitrin (3)， afzelin (4)， β-sitosterol (5)， n-hexacos-5， 8， 11-trienoic acid (6)， hexacosane (7)， α-linolenic acid (8)， kaempferol-3-O-rutinoside (9)， myristic acid (10) and quercetin (11). Conclusion: P. multiflorum leaves showed good anti-inflammatory activity， and compounds 2， 4， 6， 7， 8， 9， 10， 11 were isolated and obtained from P. multiflorum for the first time.