Objective To study the saponins of Psammosilene tunicoides. Methods The chemical constituents were extracted by 70% ethanol， then isolated by methods of macroporous resin， Sephadex LH-20 column chromatography， RP-18 column chromatography and silica gel column chromatography. The structures were established on the basis of modern spectroscopic analysis. Results Four triterpenoid saponins were isolated and characterized. Conclusion Compound 1 is obtained from the nature for the first time.