To explore extraction process of saponin and the influence of functionality in sorghum vinegar on rabbits platelet aggregation, by adopting the technologies of ultrafiltration membrane, organic solvent extraction and sephadex extraction to separate and concentrate sorghum vinegar, obtains saponin extract. The results showed that the high purity of saponin extract could be produced by the following condition: 75%vol alcohol, 30min, 50℃ extract by ultrasonic and deionized water be the moving-phase. By using ADP and collagen as inducers and rabbit blood as blood source, it can be proved that soponin extract showed strong anti-platelet aggregation function, with IC50 being (2.21±0.34) mg/ml for ADP as the inducer and (2.98±0.12) mg/ml for collagen as the inducer. Moreover, through a quantitative detection of saponin in saponin extract, data analysis of SPSS indicates that the content of saponin in saponin extract is correlated to its anti-platelet aggregation activity (p <0.01). Therefore, it can be concluded that saponin substances in Shanxi sorghum vinegar have strong activity in anti-platelet aggregation of rabbit.