Abstract: OBJECTIVE To investigate the effects of pranlukast on memory impairment induced by scopolamine in mice and its underlying mechanisms. METHODS Pranlukast(0.3, 0.6, 1.2 mg·kg^-1·d^-1) was orally administered 0.5 h after intraperitoneal injection with scopolamine (0.8 mg·kg^-1·d^-1) for consecutive 14 days. Memory function was evaluated by Morris water maze and Y maze tests. Changes in cholinergic system reactivity were also examined by measuring the acetylcholine (Ach) and acetylcholinesterase(AchE) in the hippocampus and cortex. RESULTS Treatment with pranlukast(0.3-1.2 mg·kg^-1·d^-1) significantly decreased the escape latency in hidden platform test and increased the time spent in the platform quadrant and the number of platform location crossings in the spatial probe test, and increased the correct number in Y maze test. Pranlukast also significantly increased Ach level and decreased AchE activity in the hippocampus and cortex. CONCLUSION Pranlukast may improve scopolamine-induced memory impairment through elevation of brain Ach levels resulting from inhibition of AchE activity in mice.