This study aimed to determine dose of scopolamine to induce cognitive and memory dysfunction in rat. Six-week-old male rats (n=20) were randomly divided four groups. Scopolamine bromide (0, 0.5, 1.0 and 2.0 mg/kg) was intraperitoneally injected for 7 days. From 4-7 days after injection, the rats were performed memory test by water maze and passive avoidance test. On the 8th day, the rats were sacrificed, then acetylcholinesterase (AChE) activity, cholinergic proteins and inflammatory mediators were analyzed from their brain tissue. In the memory test and AChE activity, the group of scopolamine treatment (0.5 mg/kg) showed no significant difference compared to the control group (0 mg/kg). But, they showed significant differences compared to the control group in expression of choline transporter, choline acetyltransferase, and vesicular acetylcholine transporter protein and nuclear factor kappa B, tumor necrosis factor-α, interLeukin-6, inducible nitric oxide synthase, and cyclooxygenase2 mRNA. Also, the groups of scopolamine treatment (1.0 and 2.0 mg/kg) showed significant differences compared to the control group in memory test, AChE activity, expression of cholinergic proteins and inflammatory mediators mRNA. Therefore, it was suggested that 1.0 mg/kg of scopolamine is adequate dose to induce cognitive and memory dysfunction in rats.