We conducted a neuropsychological study comparing early-stage Alzheimer's disease (AD; n = 22) and multiple subcortical infarction with mild cognitive impairment (MSI; n = 22) using an easily applicable test battery which included 8 tests. Two groups were matched for age, education and score on the Mini-Mental State Examination. Patients with AD had significantly lower scores than MSI patients in the delayed recall of the Rey-Osterrieth Complex Figure, while MSI patients had significantly worse scores in the Wisconsin Card-Sorting Test. This suggests that early discrimination of MSI from AD can be made by frontal system impairment in MSI and episodic memory disturbance in the visuospatial domain in AD using simple neuropsychological tests.