The anodic oxidation of oxalic acid on Au has been studied at 80°C in aqueous media. The reaction rate was measured as a function of potential, oxalic acid concentration, pH, and temperature in H2SO4+ K2SO4+ KOH solutions of unit ionic strength. The oxalic acid was oxidized in acidic media to CO2. A first-order dependence of the rate on both pH and undissociated oxalic acid was found. The first decarboxylation step appears to be rate determining.