A method is for operating a memory device including a plurality of memory cells disposed in regions where a plurality of first signal lines and a plurality of second signal lines cross each other. The method includes applying an initial voltage to the plurality of first signal lines, floating the plurality of first signal lines to which the initial voltage is applied, applying a second inhibit voltage to the plurality of second signal lines, and increasing voltage levels of the plurality of first signal lines to a first inhibit voltage level via capacitive coupling between the plurality of first signal lines which are floated and the plurality of second signal lines to which the second inhibit voltage is applied.