This study was aimed to search anti-platelet aggregation effectors from Gardenia jasminoides extract with the employment of platelet affinity extraction method coupled with HPLC, in order to provide pharmacological experi-mental evidences of the selected effectors to verify its feasibility. Under physiological conditions, washed rat platelets were added into G. jasminoides extract and then a mixture was gained. Consequently, some components from G. jas-minoides extract were combined to the platelets in the mixture while some were not owing to their special chemical structures and properties. Firstly, the uncombined components were washed off from the mixture. Secondly, the com-bined components in the leftover was washed down and collected, respectively, right after destroying the occupied platelets' structures. Thirdly, different collected eluents were analyzed, respectively, by HPLC established in the pre-vious work to search the effectors. Fourthly, pharmacological experiments were implemented for confirmation. The re-sults showed that dominant effective components from G. jasminoides extract acting on anti-platelet aggregation were identified as geniposide. Further evident was provided as well by pharmacological experiment that geniposide exhibit-ed significant inhibitory effect on anti-platelet aggregation in rats induced by ADP, rat tail collagen and thrombin(P< 0.01). It was concluded that the platelet affinity extraction-HPLC method proposed in this paper can be utilized to analyze the correlation of effectors from G. jasminoides extract and its pharmacological effects. Moreover, there are some correlations between screened chemical substances and their pharmacological effects.