We report x-ray photoemission spectra of the surface of iron oxide (FeO) particles. The research grade high purity FeO sample was commercially obtained from Alfa/AESAR. The XPS spectra were measured with the Physical Electroncs Model 5400 x-ray photoelectron spectrometer using unmonochromatized Mg Kα x-rays at two pass energy settings corresponding to analyzer resolutions of 1.34 and 0.54 eV. We present the survey spectrum (binding energy range of 0–1100 eV) measured at an analyzer energy resolution of 1.34 eV. Multiplexes of the C 1s, O 1s and 2s, and Fe 2p and 3p photoemission lines, valence band region as well as the Fe LVV Auger line were measured at an analyzer energy resolution of 0.54 eV. The XPS data indicate that the surface of FeO powdered material consists mainly of Fe2O3 with small quantities of FeOOH, oxidized carbon, and hydrocarbon as contaminants.