The Chongmyungtang (CMT; the combination of Acorus gramineus, polygala tenuifolia and Poria cocos) has been recognized to possess the preventive effect against several neurologic disorders in human. In this study, we examined the effect of CMT on the three parameters associated with kainic acid (KA)-induced neurotoxicities; seizure/mortality, increased fos-related antigen (FRA) and glial fibrillary acidic protein (GFAP) expression. KA induced vigorous convulsions lasting 4-6 hr. Pretreatments with CMT before KA injection significantly reduced the seizure intensity as well as the mortality. CMT pretreatments also attenuated the KA-induced increase in FRA/GFAP expression in the hippocampus. These results suggest that CMT has a neuroprotective effect against KA-induced neurotoxicities.