Abstract: OBJECTIVE To explore the protective effect of coenzyme Q10 on focal cerebral ischemic-reperfusion injured rats. METHODS Ninety adult male Sprague Dawley (SD) rats were randomly divided into 5 groups: sham-operated group (sham), ischemic-reperfusion group (I/R), Edaravone group (Y), coenzyme Q10 pre-treated low dose and high dose group (LQ and HQ). Models were established with middle cerebral artery occlusion. After 24 hours, neuroethology score and brain water content were detected. Activities of superoxide dismutase (SOD) and contents of malondialdehyde (MDA) were measured in blood serum and brain tissue from the experimental rats. The expression of Bcl-2, Bax and TNF-α protein were detected by immunohistochemistry staining. RESULTS Neuroethology score and brain water content significantly decreased in HQ group comparing with I/R group. Activities of SOD were higher and contents of MDA were lower in HQ group than I/R group in both blood serum and brain tissue. Immunohistochemistry staining showed that the positive cell number of expressing Bcl-2 significantly increased and the positive cell number of expressing Bax and TNF-α significantly decreased in HQ group compared with I/R group. CONCLUSION Coenzyme Q10 may protect rats from ischemic-reperfusion injury through scavenging free radicals and improving the anti-oxidative ability of the brain tissue and decreasing cell apoptosis and the level of inflammatory factors.