Cerebral amyloid angiopathy (CAA) is a common degenerative disease presenting intracerebral hemorrhage (ICH) in older people. Uric acid (UA) is a natural antioxidant, and may have a beneficial role in neurodegenerative diseases. Nevertheless, the role of UA in CAA remains unknown. In the present study, we compared serum UA levels in CAA-associated ICH patients (n = 82) and age/sex-matched controls (n = 82). Serum UA levels in possible CAA were significantly decreased when compared with healthy controls (232.68 +/- A 77.70 vs. 309.42 +/- A 59.83 mu mol/L; p < 0.001). Furthermore, UA levels in patients clinically diagnosed as probable CAA were significantly lower than those in patients diagnosed as possible CAA (193.06 +/- A 56.98 vs. 232.68 +/- A 77.70 mu mol/L; p = 0.014). These differences were still significant after adjusting for renal function and dyslipidemia (p < 0.001 and p = 0.002, respectively). However, there were no associations between serum UA levels and the distribution of hemorrhagic lesion, as well as neurological impairment. Our observations indicate that serum UA levels were decreased in CAA patients. UA might play a neuroprotective role in CAA and serve as a potential biomarker for reflecting the severity of A beta deposition.