Complications and mortality of heart failure are high, despite the availability of several forms of treatment. Uric acid, the end product of purine metabolism would actively participate in the pathophysiology of heart failure. However, there is no consensus about its action in cardiovascular disease. Serum uric acid would have a protective antioxidant activity. This action could help to reduce or counteract the processes that cause or appear as a result of heart failure. However, these protective properties would vanish in the intracellular environment or in highly hydrophobic areas such as atherosclerotic plaques and adipose tissue. This review discusses the paradoxical action of uric acid in the pathophysiology of heart failure.