Baicalein is one of the main active ingredients of Scutellaria baicalensis Georgi. Baicalein has many good biological activities, such as anti-inflammatory, antioxidant and anti-apoptosis. The protective effect of baicalein on myocardial ischemia and reperfusion injury was studied. The results showed that baicalein could decrease the content of MDA (malondialdehyde) and MPO (myeloperoxidase) in serum of rats and increase the level of SOD (superoxide dismutase), which was significantly different from the model group (P<0.05). The results showed that baicalein could enhance the antioxidant capacity and alleviate neutrophil mediated inflammatory injury. Compared with the model group, the SOD activity of baicalein low concentration group (25mg/kg) increased significantly (3.47±0.28). The content of MDA in myocardium of rats with high concentration of baicalein (50mg/kg) decreased significantly (425.87±19.24), whereas he GSH/GSSG ratio increased significantly (30.28+0.48), P<0.05. High concentration of baicalein preconditioning can significantly reduce the release of CK (creatine kinase) and LDH(lactate dehydrogenase) induced by myocardial ischemia/reperfusion injury, reduce the rate of myocardial infarction and reduce the rate of myocardial apoptosis.