Non-volatile memory devices highly integrated using an oxide based compound semiconductor and methods of operating and fabricating the same are provided. A non-volatile memory device may include one or more oxide based compound semiconductor layers. A plurality of auxiliary gate electrodes may be arranged to be insulated from the one or more oxide based compound semiconductor layers. A plurality of control gate electrodes may be positioned between adjacent pairs of the plurality of auxiliary gate electrodes at a different level from the plurality of auxiliary gate electrodes. The plurality of control gate electrodes may be insulated from the one or more oxide based compound semiconductor layers. A plurality of charge storing layers may be interposed between the one or more oxide based compound semiconductor layers and the plurality of control gate electrodes.