Abstract: AimTo study the basis of actions of Gualou xiebai baijiutang. MethodsGuided by bioactivities, chemical and chromatographic ways were applied to isolate and purify the prescription. The chemical structures were identified by chemical and spectral ways. The activities on cardiovascular system of the pure compounds were measured. ResultsSeven steroidal compounds were isolated and identified from the active parts. ConclusionCompounds 5 and 6 showed good anti-platelet aggregation activities induced by ADP and PAF. The IC₅₀ of compound 5 and 6 induced by 2 μmol·L^-1 ADP were 0.082 and 0.078 mmol·L^-1， and the IC₅₀ induced by 0.5 μmol·L^-1 PAF were 0.182 and 0.151 mmol·L^-1, respectively.