To destroy stored needless data efficiently with less power consumption in a semiconductor memory device consisting of ferroelectric memories.

After reading the memory region specified by an address by combination of a data destroy signal (DEL) and a chip selecting signal (/CS), it is stopped that data is rewritten in a region in which data is destroyed by its reading operation by lowering the potential of a plate line after a bit line is pre-charged to the ground potential. At the time, such constitution may be permitted that the potential of a word line is held at a VDD level without boosting it to a potential for rewriting data. Also, such constitution may be permitted that outputting read out data to the outside is stopped and the operation of a sense amplifier is stopped by clamping a bit line to the ground potential.