This study aimed to investigate the neuroprotective effect of Triptolide (T10) on cerebral ischemia/reperfusion (I/R) injury and explore the underlying mechanisms. Adult male Sprague-Dawley rats were treated with T10 and subjected to middle cerebral artery occlusion (MCAO) for 90 min. Neurological deficits and infarct volume were measured 24 h after reperfusion. ER stress-mediated proteins, ryanodine receptors (RyRs), cysteinyl aspartate specific proteinase 8 (Caspase-8), Fas-associated death domain (FADD) and C/EBP homologous protein (CHOP) were evaluated 1, 4, and 24 h after reperfusion. Pretreatment with 1 mg/kg of T10 significantly reduced infarct volume and neurological deficits. Further, TUNEL staining demonstrated T10 significantly decreased neuronal apoptosis in the peri-infarct area after reperfusion. More importantly, T10 prevented ER stress-mediated expression of RyR, FADD, caspase-8 and CHOP in the peri-infarct area of rats. These results indicate that T10 attenuates the ER stress-induced apoptosis in cerebral I/R injury and suggest that T10 is a promising agent for the treatment of ischemic stroke.