We report the dependence of electrical properties of Fe-O-N thin films on the deposition condition as well as on O 2 and N 2 gas flow rate. Fe-O-N films were deposited by reactive sputtering using O 2 and N 2 as reactive gas. The electrical resistivity of Fe-O-N films increased with increasing O 2 and N 2 gas flow rate. The resistivity increase with the O 2 flow rate was due to structure change from a mixed phase of metallic Fe+Fe 3 O 4 , to a mixed phase of FeO+¡-Fe 2 O 3 , and to a single phase of ¡-Fe 2 O 3 , as evidenced by XPS analysis of Fe 2p core excitation peaks. Meanwhile, the resistivity increase with the N 2 flow rate was due to structure change from a metallic Fe, to a mixed phase of metallic Keywords: iron oxide, nitrogen-doped, electrical resistivity, effects of oxygen and nitrogen flow rate