Objective: To Explore mechanism of Buyanghuanwutang and its separate groups resisting cerebral ischemia in ischemic-reperfusion lesion. Methods: The ischemic-reperfusion model of four cerebral artery occlusion of SD rat was prepared, and the influence of the Buyanghuanwutang, its separate groups astragalus and promoting circulation group on the content of TXB 2 、6-Keto-PGF 1a in serum of the model were observed.Results: Model rats had high content of TXB 2,low level of 6-Keto-PGF 1a in serum. In the groups of Buyanghuanwutang, astragalus, and promoting circulation group the content of 6-Keto-PGF 1a increased, TXB 2 decreased, general prescription had the most notable effect.Conclusion: Through influencing the contents of metabolic materials of tetra-olefine acid- TXB 2 and 6-keto-PGF 1a, Buyanghuanwutang and its separate groups can have the effects of resisting cerebral ischemic-reperfusion lesion.The effect of general prescription is better than that of its separate groups.