Objective: To observe the effects of the compounds from gastrodia on anti-platelets aggregation induced by AA in vitro and define its material base. Methods: Anti-platelets aggregation effects of B、C、D separated from the ethyl acetate extracted parts of Gastrodia elata Blume and gastrodin were observed by light transmission in vitro. AA was used as inducers. Results: Compounds B、C、D all had some effects on anti-platelets aggregation at high concentration(04 mg·mL-1), IC50 is 0104、0163、0263mg·mL-1. The inhibition of compound B was much stronger and presented certain concentration dependence. Gastrodin had no significant effects on rabbit blood platelets aggregation induced by AA in vitro. Conclusion: Compounds B、C、D all had some effects on anti-platelets aggregation, among which, compound B was much stronger. Gastrodin had no significant effects at the same concentration.