METHODS AND RESULTS:To study the chemical constituents from the rhizome of Menispermum dauricum,fifteen compounds, N-Methylcorydalmine(1),thalifoline(2),stepholidine(3),acutumine(4),daurisoline(5),acutumidine(6),dauricicoline(7),bianfugecine(8),6-O-demethylmenisporphine(9),bianfugedine(10),dauricoside(11),eleutheroside D(12),aristolactone(13),aristoloterpenateⅠ?(14) and aristolochic acid(15) were isolated from 75% ethanol extract of Menispermi Rhizoma by using thin layer chromatography and column chromatography methods. Their structures were identified based on their physicochemical properties and spectral data. Among them,compounds 12-15 were obtained from the genus Menispermum for the first time. Six alkaloids with higher contents were subjected to evaluate the anti-hypoxic activities by using MTT method. CONCLUSIONS: As a result,six alkaloids exhibited significant anti-hypoxia activities.