Objectives : The purpose of this study was to characterize the effect of the Ethanolic extract of Stachys sieboldii and Lycopus lucidus on the learning and memory impairments induced by scopolamine. Methods : The genetic difference of Stachys sieboldii and Lycopus lucidus were observed with RAPD analysis. The cognition-enhancing effect of Stachys sieboldii and Lycopus lucidus was investigated using a passive avoidance test, Y-maze test and the Morris water maze test in mice. Drug-induced amnesia was induced by treating animals with scopolamine (1 mg/kg, i.p.). Results : As a result of RAPD analysis, Stachys sieboldii and Lycopus lucidus Radix was found to be genetically different and The results of learning memory analysis showed that Stachys sieboldii extract-treated group (500 mg/kg, p.o.) and the tacrine-treated group (10 mg/kg, p.o.) significantly ameliorated scopolamine-induced amnesia based on the Passive avoidance Y-maze test and Water maze test. And these results are same manner in DPPH radical scavenger effect and Acetylcholineseterase inhibition effect. These results suggest that Stachys sieboldii extract maybe a useful cognitive impairment treatment, and its beneficial effects are depending on the origin plants. Conclusions : Commercially available Stachys sieboldii Radix consists of two original plant, one of them people misuse. To clarify the origin of the plant Memory tests were performed. These results suggest that 80% Ethanol extract of Stachys sieboldii showed significant anti-amnestic and cognitive-enhancing activities related to the memory processes, and these activities were parallel to treatment duration and dependent of the learning models.