Objectives: This study was performed to evaluate the neurototoxicity of the environmental pollutant lead acetate(LA) and the protective effect of the D-2-amino-5-phosphonovaleric acid(APV), N-methyl-D-aspartate(NMDA) receptor antagonist on LA-induced cytotoxicity in cultured C6 glioma cells. Materials and Methods: For this study, cell viability in cultured C6 glioma cells was assessed by XTT assay and antioxidative effect, such as lactate dehydrogenase(LDH) activity, by LDH detection kit. Results: LA significantly decreased cell viability in a dose-dependent manner, and the XTT50 value was determined to be 33.3 uM of LA. The cytotoxicity of LA was deemed highly toxic according to Borenfreund and Puerner`s toxic criteria. The vitamin E antioxidant significantly increased cell viability damaged by LA-induced cytotoxicity in these cultures. For the protective effect of APV on LA-induced cytotoxicity, APV significantly increased not only cell viability, but also inhibition of LDH activity. From these results, it is suggested that oxidative stress is involved in the neurotoxicity of LA, and APV effectively protected against LA-induced cytotoxicity via an antioxidative effect as an inhibotory activity of LDH. Conclusions: Natural resources like APV may be putative therapeutic agents for the toxic diminution of environmental pollutants such as LA correlated with oxidative stress.