OBJECTIVE: To evalute the effects of TAK-147, a novel acetylcholinesterase inhibitor on rat spatial memory deficit using the Morris water maze. METHODS: Morris water maze was used to measure spatial memory in rats, and open field test was used to analysis locomotor activity. RESULTS: Scopolamine (0.4mg/kg,IP) significantly increased the latency period in memory acquisition. Intraperitoneal TAK-147 injection ameliorated scopolamine-induced deficit in a dose-related manner. A significant effect was obtained at doses of 0.3 and 1.0 mg/kg. Both TAK-147 (0.3 and 1.0 mg/kg) and tacrine (3 and 5 mg/kg) significantly reversed scopolamine (1.5 mg/kg) increased latency in memory retrieval. However, TAK-147 had a more potent effect than tacrine. In the locomotor test, TAK-147 created no appreciable change, compared with scopolamine or saline. CONCLUSION: A novel acetycholinesterase inhibitor, TAK-147 ameliorates the scopolamine induced impaired spatial memory in rats.