The purpose of this research was to investigate the effects of Bojunglkgi-tang water extract (BE) on the specific immune response in BALB/c mice. When BE (500mg/kg) was administerd p.o. once a day for 7 days to BALB/c mice, the cell viability of splenocytes was increased and DNA fragmentation of splenocytes was decreased. But, BE did not affect the cell viability and DNA fragmentation of thymocytes. Also, BE increased the population of Thy1⁺ cells and TH cells in splenocytes. In addition, BE increased the production of γ -interferon from splenocytes. These results suggest that BE enhances the specific immune response via activation of TH1 cells in splenocytes.