Buyang Huanwu Decoction (BYHWD) is a well-known traditional Chinese medicine prescription which is used to treat ischaemic stroke and stroke-induced disabilities. However, the exact mechanism underlying BYHWD's amelioration of ischaemic stroke and its effective constituents remain unclear. The present study aimed to identify the effective constituents of BYHWD and to further explore its action mechanisms in the amelioration of ischaemic stroke by testing the activities of 15 absorbable chemical constituents of BYHWD with the same methods under the same conditions. The following actions of these 15 compounds were revealed: 1) Ferulic acid, calycosin, formononetin, astrapterocarpan-3- O-β-D-glucoside, paeonol, calycosin-7- O-β-D-glucoside, astraisofla-van-7- O-β-D-glucoside, ligustrazine, and propyl gallate significantly suppressed concanavalin A (Con A)-induced T lymphocyte proliferation; 2) Propyl gallate, calycosin-7- O-β-D-glucoside, paeonol, and ferulic acid markedly inhibited LPS-induced apoptosis in RAW264.7 cells; 3) Propyl gallate and formononetin significantly inhibited LPS-induced NO release; 4) Hydroxysafflor yellow A and inosine protected PC12 cells against the injuries caused by glutamate; and 5) Formononetin, astragaloside IV, astraisoflavan-7- O-β-D-glucoside, inosine, paeoniflorin, ononin, paeonol, propyl gallate, ligustrazine, and ferulic acid significantly suppressed the constriction of the thoracic aorta induced by KCl in rats. In conclusion, the results from the present study suggest that BYHWD exerts its ischaemic stroke ameliorating activities by modulating multiple targets with multiple components.