Previous experimental studies have shown that cerebral infarction can be effectively reduced following treatment with scutellaria baicalensis stem-leaf total lfavonoid (SSTF). However, the mechanism of action of SSTF as a preventive drug to treat cerebral infarction remains unclear. In this study, Sprague-Dawley rats were pretreated with 50, 100, 200 mg/kg SSTF via intragastric ad-ministration for 1 week prior to the establishment of focal cerebral ischemia/reperfusion injury. The results showed that pretreatment with SSTF effectively improved neurological function, re-duced brain water content and the permeability of blood vessels, ameliorated ischemia-induced morphology changes in hippocampal microvessels, down-regulated Fas and FasL protein expres-sion, elevated the activity of superoxide dismutase and glutathione peroxidase, and decreased malondialdehyde content. In contrast to low-dose SSTF pretreatment, the above changes were most obvious after pretreatment with moderate-and high-doses of SSTF. Experimental ifndings indicate that SSTF pretreatment can exert protective effects on the brain against cerebral isch-emia/reperfusion injury. The underlying mechanisms may involve reducing brain water content, increasing microvascular recanalization, inhibiting the apoptosis of hippocampal neurons, and attenuating free radical damage.