Cerebral amyloid angiopathy (CAA) occurs commonly in the elderly population. It results in thickening of the vessel wall, primarily in small arteries and arterioles of the leptomeninges and cerebral cortex. Primary intracerebral hemorrhage (ICH) in the elderly is the result of disease of the small cerebral vessels, in particular hypertensive vasculopathy or CAA. The CAA-related cerebral microbleeds (CMBs), like other types of microbleed, consist primarily of macrophages containing hemosiderin, a degraded form of ferritin. The most commonly employed criteria for diagnosis of CAA-related ICH are based on neuropathological examination or, more commonly, characteristic neuroimaging findings. Despite its high age-related prevalence, CAA has been difficult to detect non-invasively and is, likely to be underestimated in its effects on the aging process. The occurrence of CAA-related CMBs has emerged as the most useful diagnostic marker for CAA in clinical practice and investigation.