Cerebral amyloid angiopathy (CAA) is characterized by the deposition of -amyloid protein in the media and adventitia of small arteries and capillaries. It may be an independent disease, but is often combined with Alzheimer's disease (AD). This review will discuss up-to-date understanding of the pathophysiology, clinical manifestations of CAA, its diagnosis with neuroimaging and biomarkers. Cerebral microbleeds (CMBs) may be considered as neuroimaging markers of AD and CAA. The clinical significance of CAA is defined by the risk of intracerebral hemorrhages during thrombolytic therapy and warfarin therapy in patients with acute myocardial infarction, pulmonary embolism, ischemic stroke.