Background: Attention is too difficult to measure quantification due to the numerous affected variables. Attention Questionnaire Scale (AQS) is a newly developed scale for the evaluation of the patient’s attention. The aim of this study was to adapt AQS to evaluate the correlation between attention and subcortical hyperintensities (SH) to the patients with mild to moderate Alzheimer disease (AD) or subcortical vascular dementia (SVD). Methods: Patients with mild to moderate AD or SVD were recruited from March 2008 to February 2010. On magnetic resonance imaging, deep white matter (DWM) hyperintensities were classified into D1 (the longest diameter of DWM lesion <10 mm), D2 (10 mm≤DWM≤24 mm), and D3 (25 mm <DWM). Likewise, periventricular white matter (PWM) hyperintensities were classified into P1 (caps or rim <5 mm), P2 (between P1 and P2), and P3 (10 mm <caps or rim). The SH was divided into three groups according to the combinations of DWM and PWM hyperintensities: minimal (D1P1, D1P2, D2P1), severe (D3P3), and moderate hyperintensities group with hyperintensities of remaining combinations. AQS, Korean version of Mini-Mental Status Examination (K-MMSE), Clinical Dementia Rating (CDR) and Global Deterioration Scale (GDS) were performed in all the patients. Patients with mild to moderate AD or SVD were divided into three groups according to the SH (minimal, moderate and severe SH group). We evaluate AQS, K-MMSE, CDR and GDS according to the degree of SH. Results: A total of 162 study patients were recruited (87 in minimal, 22 in moderate and 53 in severe SH group). Female was predominant in all three groups (66.7%). Mean score of K-MMSE was 17.5±5.7 and that of the CDR was 1.3±0.9. Mean score of AQS was 17.1±7.9. The correlation between AQS and other scales such as K-MMSE, CDR and GDS were all significant (the correlation coefficiency was 0,317, -0.474, -0.472, respectively). Unlike other scales AQS showed significant differences between minimal and moderate or severe SH group (18.7±7.7, 15.2±6.6, 15.4±8.6, p=0.007). Conclusions: AQS is a useful dementia scale for the evaluation of the degree of SH in the patients with mild to moderate AD or SVD.