Objective : The purpose of this study is to investigate the effect of Radix Scutellariae on repeated nicotine-induced locomotor activity and c-Fos expression utilizing Fos-like immuno-histochemistry method in the nucleus accumbens, and the striatum, one of the major projection areas of the control DA system. Methods : Male Sprague-Dawley rats were divided into untreated(normal), nicotine-treated (control), Radix Scutellariae-treated(sample) groups, RS group received Radix Scutellariae(100mg/kg, i.p.) 30minutes before injection of nicotine(0.4mg/kg, s.c.) for 7days. Rat were followed withdrawal for 3 days and one challenge for 1day. Results : Systemic challenge with nicotine produced a much larger locomotor activity and expression of c-Fos in the nucleus accumbens and the striatum. Pretreatment with Radix Scutellariae decreased in nicotine-induced locomotor activity and c-Fos expression in the core, shell, straitum area. Conclusion : These results demonstrated that reduction in locomotor activity by Radix Scutellariae may be mediated by reduction of dopamine release and of postsynaptic neuronal activity in striatum, the nucleus accumbens. Out results show neurochemical evidence for the biological effects of Radix Scutellariae that ultimately may help us to understand how Radix Scutellariae can be used to treat nicotine addiction.