A nonvolatile memory apparatus includes a sensing voltage generation unit, a memory cell, a current copy unit and a data sensing unit. The sensing voltage generation unit provides a sensing voltage with a constant level, to a sensing node. The memory cell receives the sensing voltage from the sensing node. The current copy unit generates copied current with substantially the same magnitude as sensing current which flows through the memory cell. The data sensing unit senses the copied current and generates a multi-bit data output signal.