Objective: To study the effects of the alcohol extract of Loulu (AEL) on the ability of learning and memory in mice and on the activity of cholinesterase in brain and whole blood.Methods: In order to establish the effect of the alcohol ectract of Loulu on the ability of learning and membory in mice, the methods of one trial passive avoidance response(step down test) were used. Results: The AEL could antagonize the acquisition impairment of memory induced by scopolamine (SCPL) and the consolidation disruption of memory elicited by cycloheximide (CYC), inhibit the activity of cholinesterase in brain and whole blood. Conclusion: The improving effect of the AEL on the ability of learning and memory might be related with its effect of improving function of the central cholinesterase system.