Dependence of initial oxidation behavior on crystalline orientation of Haynes 230 at 900 degrees C was investigated by a novel method. Analysis of oxidation rate reveals that the oxide thicknesses are different for grains having different orientations. Orientation mapping was performed on oxidized specimen and grains having near {1 1 1} were easily indexed by electron backscattered diffraction. We determined that planes with deviation angle lower than 20 degrees were all well indexed after oxidation. Results demonstrate that substrate orientation plays an important role on oxidation rate during the initial stage. (C) 2014 Elsevier B.V. All rights reserved.