A non-volatile memory device is provided to sense a bit lien voltage by using a sensing transistor having a high threshold voltage. A sensing circuit(300) determines the erase state or the programming condition of a target memory cell transistor. A sensing circuit comprises a sensing transistor(360) and a gate receiving the voltage of a bit line while having high threshold voltage. The threshold voltage of the sensing transistor is lower than the voltage applied to the bit line for reading connected to the transistor of the target memory cell. The threshold voltage of the sensing transistor is higher than the saturation voltage level of the bit line for reading. The sensing transistor is turned on the erase state of the transistor of the target memory cell transistor.
