The relation between pulse pressure (PP) and Alzheimer disease (AD) remains unclear. We performed this study to investigate the relation between PP and AD and the impact of PP to impair cognitive performance on this relationship. It is a cross-sectional study from the Neurology Memory Clinic of Chungnam National University Hospital and five senior welfare centers in the city of Taejon, Korea. A cohort of 75 patients with AD and 117 control subjects were enrolled for the study. PP was significantly higher whereas mean arterial pressure (MAP) was lower in patients with AD than those of control subjects. Elevated serum total cholesterol (TC) level was significantly associated with both PP and MAP in control subjects as well as patients with AD. We found a significant relationship between PP and cerebral white matter changes (WMCs) in AD. PP changes correlate with leukoaraiosis in AD.