According to the theory of Traditional Chinese Medicine, the main etiology of stroke results from blood stasis. Ligustic Rhizoma (LR), a Chinese herb, is considered to stimulate stasis-dispelling. As Tetramethyl Pyrazine (TMP) is a major component of LR, the aim of the present study is to investigate the effects of TMP on cerebral infarct. We establish an animal model of cerebral infarct by occluding the both common carotid arteries and right middle cerebral artery for 90 minutes, then reperfusing for 24 hrs. Effects of TMP on cerebral infarct are evaluated by the ratio of infarction areas and modified neurologica severity scale (mNSS). In addition, we observe the changes of ED1, tumor necrosis factor-£\ (TNF-£\) and interleukin-1£] (IL-1£]) immuno-reacting cells in the infarction region. The founding indicate that pre-treatment with TMP 100 mg/kg, 120 mg/kg and 140 mg/kg, and post-treatment with TMP 100 mg/kg will decrease the ratio of cerebral infarction area and the neurological deficit. Moreover, pre-treatment TMP 100 mg/kg also decreases ED1, TNF-£\ and IL-1£] immuno-reacting cell. In conclusion, TMP can decrease cerebral infarction area and neurological deficit. The effects of TMP, at least in part, are closely related to microglia, TNF-£\ and IL-1£], suggesting that TMP can be used to treat stroke in human.