Provided are a non-volatile memory device and a method of operating the non-volatile memory device. The non-volatile memory device includes a switching device and a storage node connected to the switching device, wherein the storage node comprises: a first electrode connected to the switching device; a chalcogenide material layer formed on the first electrode; and a second electrode formed on the chalcogenide material layer, and one of the first and second electrodes comprises an electrode contact layer formed adjacent to a limited region of the chalcogenide material layer, and a property of the electrode region adjacent to the chalcogenide material layer is changed reversibly according to the direction in which a current is applied, thereby changing between a high resistance state and a low resistance state.