Oxidation of 304L stainless steel in a carbon dioxide atmosphere at 10 5 Pa has been studied. Between 1193 and 1293K the oxidation kinetics exhibit first a rapid increase, then a parabolic behaviour with apparent activation energy of (209±8) kJmol −1 and obeys a Langmuir pressure law. After 1.15mgcm −2 , the kinetics become almost linear.The reaction products are chromia at the grain boundaries, wüstite (Fe 1− x O) on the surface for weight gains greater than 0.30mgcm −2 and chromite. The very complex reaction mechanism takes into account random buckling for weight gains >1.15mgcm −2 .