Electro-resistance element, electro-resistance memory using the same and method of manufacturing the same

An electro-resistance element that has a different configuration from conventional elements and is excellent in both affinity with semiconductor manufacturing processes and resistance change characteristics is provided. An electro-resistance element has two or more states in which electric resistance values between a pair of electrodes and is switchable from one of the two or more states into another by applying a predetermined voltage or current between the electrodes. The electro-resistance element includes a substrate and a multilayer structure disposed on the substrate, the multilayer structure includes an upper electrode, a lower electrode and an electro-resistance layer disposed between the electrodes, wherein the electro-resistance layer includes Fe2O3, and Fe3O4 contained in an amount of 0% to 20% of Fe2O3 in percent by weight, the lower electrode is made of an iron oxide having a different composition from the electro-resistance layer and containing Fe3O4, and the electro-resistance layer and the lower electrode make contact with each other.