Abstract: Obj ective To investigate the brain-protective mechanism of Danhong inj ection in rats with acute cerebral infarction.Methods 30 rats of acute cerebral infarction models was es-tablished by means of occlusion of middle cerebral artery and randomly divided into Sham-operation group,operation group and operation plus Danhong group,10 cases in each group.The superoxide dismutase (SOD),glutathion peroxidase (GSH-Px)activities and the malondiadehyde (MDA) content in the cerebral tissue were determined after 5 d.Meanwhile the neurological function,Brain water content and histopathologic examination were observed.Results The SOD and GSH-Px activities in the operation plus Danhong group increased obviously,while the MDA content de-creased significantly compared with the operation group (P<0 .0 1 ).Moreover,there were slighter pathological changes in brain tissues.Conclusion Danhong inj ection has a certain protective effects on damage of brain tissues,which is possibly related to increased SOD and GSH-Px activities,and decreased MDA content.