Glutamate-induced oxidative injury contributes to neuronal degeneration in many central nervous system (CNS) diseases, such as Parkinson’s disease, Alzheimer’s disease, epilepsy and ischemia. Inducible heme oxygenase (HO)-1 acts against oxidants that are thought to play a role in the pathogenesis of these diseases. The EtOH extracts of Viola mandshurica (NNMBS274), Viola patrinii (NNMBS275) and Viola papilionacea Pursh (NNMBS276), origin plants of Violae Herba, showed the potent neuroprotective effects on glutamate-induced neurotoxicity. Among them, NNMBS275, the extract of V. patrinii possessed the protective effects against glutamate toxicity by inducing the expression of heme oxygenase (HO)-1 in the mouse hippocampal HT22 cells. These results suggest that extracts of V. patrinii could be the effective candidates for the treatment of ROS-related neurological diseases. Furthermore, it is suggested that the protective effects of V. patrinii extract due to inducing the expression of HO-1 as an antioxidant/cytoprotective target