A semiconductor storage device is provided with a gate electrode, a semiconductor layer, a gate insulating film sandwiched between the gate electrode and the semiconductor layer, a channel region under the gate electrode, diffusion regions provided respectively on two sides of the channel regions and being of the other conductivity region than the channel region, memory elements 1 provided respectively on two sides of the gate electrode and having a function of holding charges, and a word line driver circuit, in which the CMOS technique is used. The driver circuit includes a common node for supplying a potential for activating an output inverter for driving a row word line. While the semiconductor storage device is in a read mode, a CMOS inverter other than the output inverter controls a signal at the common node, the CMOS inverter connected to a read input line. While the semiconductor storage device is in writing/erasing mode, a plurality of writing/erasing transistors connected in series to the node are activated in accordance with an address signal, in order to lower the common node to a low potential.