Abstract: In a study of oxidation of tartaric acid with ceric sulfate,a value of 8 was obtained for the oxidation equivalent of the organic acid,different from the reported values.Conditions for this oxidation have been studied,the optimal amount of ceric sulfate and sulfuric acid was deter- mined. From the number of equivalent 8,it is postulated that one mole of tartaric acid gives upon oxidation 3 moles of CO₂ and 1 mole of HCOOH in a 2-step reaction,tartronic acid being the intermediate.