This study was performed to investigate the antithrombotic activity and protective effect of hexane fraction of Kamihyulbuchukeotang (KHCTH) on brain injury by KCN and MCA occlusion a prescription of HCT added with Lumbricus and Notoginseng Radix. Experiemental parameters are brain ischemia by MCA occlusion assay, KCN-induced brain injury, pulmonary thrombosis and platelet aggregation assay. The results were summarized as follows; 1. KHCTH extracts significantly inhibited the duration of KCN-induced coma (67%) and mortality (80%). 2. KHCTH extracts significantly suppressed brain ischemic area and edema following MCA occlusion and protected neuron cells as compared with control data. 3. KHCTH extracts inhibited pulmonary thrombosis induced by collagen and epinephrine. 4. KHCTH extracts inhibited platelet aggregation induced by collagen, ADP as agonist up to 76.9% and 32.3% respectivey at 1 mg/ml more effective than water extract of KHCT These data suggested that KHCTH could be applied as the protector of brain ischemia and injury and antithrombotic agent.