An elevated uric acid level is associated with cardiovascular disease. Hyperuricemia is predictive for the development of both hypertension and coronary artery disease; it is increased in patients with hypertension, and, when present in hypertension, an elevated uric acid level is associated with increased cardiovascular morbidity and mortality. Serum uric acid level should be measured in patients at risk for coronary artery disease because it carries prognostic information. Hyperuricemia is caused by decreased renal excretion. In this article, we suggest that this may be mediated by intrarenal ischemia with lactate generation and the inhibition of the secretion of urate by the anion-exchange transport system. The possibility that hyperuricemia directly contributes to cardiovascular or renal disease needs to be reconsidered. Although hyperuricemia is associated with a number of cardiovascular or renal risk factors, several studies have found uric acid level to be independently associated with increased mortality by multivariate analysis. If hyperuricemia is directly toxic, the most likely site is the kidney. Chronic hyperuricemia is strongly associated with chronic tubulointerstitial disease, and many of these patients have decreased renal function. Although it is possible that the hyperuricemia could simply be the consequence of the renal disease, further studies are necessary to rule out a pathogenic role for uric acid in the development of renal disease and salt-dependent hypertension.