It has been suggested that oxidative stress may play an important role in the pathogenesis of diabetic complications. The purpose of this study was to examine the oxidative stress of streptozotocin(STZ) in the cultured mouse cerebral neurons and the preventing effect of vitamin E and and Benincasae Semen(BS) on STZ-induced neurotoxicity. Cytotoxic effect of STZ and neuroprotective effect of antioxidant and BS were performed by MTT assay. 30 μM STZ decreased cell viability in dose-and time-dependent mannner, and vitamin E and BS diminished STZ-induced neurotoxicity in these cultures. From above the results, STZ has toxic effect. and antioxidants, vitamin E or herb extract of BS is very effective against STZ-induced neurotoxicity in cultured cerebral neurons of neonatal mouse.