Oxidation is an important phenomenon for materials used at high temperatures. Generally, nickel based superalloys are preferred as metallic materials due to their superior mechanical properties for high temperature applications. Inconel 718 has wide usage fields in high temperature applications. In present study, Inconel 718 and Inconel 718/Yttria (%8 Y2O3) Stabilized Zirconia (YSZ)/ Gd2Zr2O7 (GZ) was oxidized in open air atmosphere at 1000 degrees C for 8, 24 and 100 h. Isothermally oxidized samples were investigated using Scanning Electron Microscopy (SEM), x-ray Diffraction (XRD) and energy dispersive x-ray spectrometry (EDX)-SEM. Results show that Inconel 718 is not suitable for long periods at 1000 degrees C. Ceramic coated Inconel 718 exhibit better performance and it assist to see phase distributions in microstructure.