To study the chemical constituents of Oenothera biennis L..The chemical constituents from 50% acetone extract of the O. biennis were isolated by repeated chromatograph with silica gel,Sephadex LH-20,MCI gel CHP-20 and semi-preparative RP-HPLC.The structure of the separated chemical components was identified by modern spectroscopy identification.Ten compounds were isolated from the ethyl acetate fraction of 50% acetone extract of O. biennis,and identified as dimethyl 3-lactyl shikimate (1),methyl shikimate (2),3,3′,4-O-triomethylellagic acid (3),3,3′-dimethylellagic acid (4),3,4,3′-trimethoxy flavellagic acid (5),alternariol 9-methyl ether (6),2,3-dihydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl)-1-propanone (7),scirpyrone H (8),dimethoxydimethylphthalide (9),clearanol C (10).Compound 1 was a new shikimate derivative and compounds 2-10 were newly isolated from the O. biennis. Compounds 2 and 3 could significantly increase the viability of BEAS-2B cells induced by TGF-β1,showing potent lung protection.