Object : The present experiments were designed to study on the memory enhancement of the extract of Gongjadaesungjichimjung-bang(GDJB). Methods : The water extract of GCJB has been tested for its activities on memory enhancement by passive avoidance task in vivo and for its inhibitory effect on the acetylcholine esterase activity. Results : GDJB water extract significantly enhanced the memory at a concentration of 50mg/kg, but this effect did not proportionally increased at a dose of l00mg/kg and significantly inhibited the acetylcholine esterase activity in a dose-dependent manner in in vitro assay with IC50 value of 1.57mg/ml and also in in vivo assay. Conclusion : The extract of GDJB showed a memory enhancement as well as the inhibitory effect on acetylcholine esterase activity, which suggest that this prescription may be applied for the treatment of memory impairment.