A resistance changing device includes a resistive layer of a hetero structure interposed between a lower electrode and an upper electrode, and including a plurality of resistive material layers, each having a different resistivity, stacked therein, wherein resistivities of the resistive material layers decrease from the lower electrode toward the upper electrode. Since the resistive layer has a hetero structure in which a plurality of resistive material layers, each having a different resistivity, are stacked in such a manner that the resistivity decreases as it goes from the lower electrode to the upper electrode, it is possible to improve the distributions of the set/reset voltage and the set/reset current, while reducing a reset current of a resistance changing device at the same time.