Panaxynol and ginsenosides Ro, Rg1, and Rg2 were found to be the main antiplatelet components in the diethyl ether and 1-butanol fractions, respectively, during the activity-guided fractionation of Panax ginseng, Panaxynol inhibited the aggregation, release reaction, and thromboxane formation in rabbit platelets while ginsenosides Ro, Rg1, and Rg2 suppressed the release reaction only.