Nootropic acitivity of essential oil of Nepeta cataria (EONC) was studied in mice. Elevated plus maze and passive avoidance paradigm were employed to evaluate learning and memory parameters. Scopolamine (0.4 mg/kg, i.p.) was used to induce amnesia in mice. The essential oil (1gm/kg) significantly attenuated amnestic deficits induced by scopolamine (0.4 mg/kg, i.p.) and natural aging. Also exhibited decreased the transfer latencies and increased step down latencies significantly in the aged mice and scopolamine induced amnesic mice as compared with Piracetam (200 mg/kg, i.p.). To delineate the possible mechanism through which Nepeta cataria elicits the anti-amnesic effects, we studied its influence on central cholinergic activity by estimating the whole brain acetylcholinesterase activity. EONC significantly decreased acetyl cholinesterase activity in mice. The results indicate that essential oil of Nepeta cataria might prove to be a useful memory restorative agent in the treatment of dementia seen in elderly. The underlying mechanism of action may be attributed to its anti acetylcholinesterase property.