The chemical constituents from roots of Stephania tetrandra and their anti-liver fibrosis activity were studied.The roots of Stephania tetrandra were extracted with EtOH,and the extractions were separated on column chromatography of silica gel,Sephadex LH-20,ODS and semi-preparative HPLC to yield 13 compounds.According to the physical and chemical properties and spectral data,13 compounds were identified as cyclanoline (1),coclaurine (2),5-hydroxymethyl-1-[2-(4-hydroxyphenyl)-ethyl]-1H-pyrrole-2-carbaldehyde (3),isosalsoline (4),thalifoline (5),northalifoline (6),2-methyl-3-hydrox ypyridine (7), (+)-lyoniresinol (8),icariside B5 (9),syringic acid (10),4-hydroxyphenylacetic acid (11),4-hydroxybenzoic acid (12),p-hydroxyphenylacetic acid methyl ester (13).Compounds 1-13 are isolated from this plant for the first time.And compounds 3,4,6-9 have never been reported before from the genus Stephania. The compounds 1-13 were preliminarily examined for anti-liver fibrosis activity.Compounds 2,5,6,10-12 showed antiproliferative activities in LX-2 induced by TGF-β1.