Disclosed is an application of piceatannol-3-O-β-D-glucopyranoside in the preparation of medicaments for improving microcirculation block. The medicaments comprise piceatannol-3-O-β-D-glucopyranoside of formula (I) as active ingredients:and one or more pharmaceutically acceptable additives, especially of gastrodin and/or water soluble cyclodextrin derivatives, or PEG400 and mannitol. The invention also discloses applications of piceatannol-3-O-β-D-glucopyranoside as active ingredients in the preparation of medicaments for improving block induced by brain microvascular injury and/or block induced by ischemical reperfusion injury and/or block induced by leucocyte adherence and/or block induced by peroxides. The invention tests the effects of medicaments by tail intravenous injection with Kunming normal mice and model mice with microcirculation block induced artificially. The capillary vessel net and the shrinkage of arteriole and venule are observed under microcirculation microscope. The test shows that: the medicament has obvious expansion effect on blood vessels of the normal mice, can evidently antagonize the shrinkage of arteriole and venule and the reduction of the open number of capillary vessel net of the model mice with microcirculation block, and can obviously confront the blood flow slowing.
