[Objective] To investigate the chemical constituents from the ethanol extracts of Cynanchum ascyrifolium. [Methods] The compounds were isolated and purified by ODS,macroporous resin chromatography,preparative HPLC methods and so on. Their structures were elucidated by their physical properties,mass spectrometry,and nuclear magnetic resonance spectrum.[Results]Four seco-pregnane-type steroids were isolated from the ethanol extracts of C. ascyrifolium; they were identified to be glaucogenin-A( 1),glaucogenin-C 3-O-β-D-thevetoside( 2),glaucogenin-C 3-O-β-D-oleandropyranoside( cynatratoside-A,3),and glaucogenin-A 3-O-β-D-digitoxopyranosyl-( 1 →4)-β-D-cymaropyranoside( cynanversicoside F or sublanceoside B2,4).[Conclusions] The four compounds were obtained from C. ascyrifolium for the first time. [Methods] The investigations were chemical constituents from the extracts of Cynanchum ascyrifolium. [Methods] The compounds were isolated and purified by ODS, macroporous resin chromatography, preparative HPLC methods and so on. Their structures were elucidated by their physical properties, mass spectrometry , and nuclear magnetic resonance spectrum. [Results] Four seco-pregnane-type steroids were isolated from the extracts of C. ascyrifolium; they were identified to be glaucogenin-A (1), glaucogenin-C 3-0- -thevetoside (2), glaucogenin-C 3-O-β-D-oleandropyranoside (cynatratoside-A, 3), and glaucogenin-A 3-O- β-D-digitoxopyranosyl- (1 → 4) cymaropyranoside (cynanversicoside F or sublanceoside B2,4). [Conclusions] The four compounds were obtained from C. ascyrifolium for the first time.