A non-volatile memory device having a hidden cell located separate from data storage cells, and a method of effectively managing an erase count of the non-volatile memory device. The method includes preparing the non-volatile memory device that includes a hidden cell located separate from data storage cells and is not accessible to users of the data storage cells, and increasing an erase count stored in an erase count storing region of the hidden cell corresponding to at least one erased data storage cell when the at least one data storage cell is erased.