The semiconductor storage device of this invention includes memory cells each having two transistors and one storage capacitor. Each memory cell is connected with a first word line and a first bit line for a first port and a second word line and a second bit line for a second port. The first and second bit lines are alternately disposed in an open bit line configuration. In the operation of the semiconductor storage device, in a period when a first precharge signal for precharging each first bit line or a first sense amplifier activating signal for activating a first sense amplifier is kept in an active state, a second precharge signal for precharging each second bit line and a second sense amplifier activating signal for activating a second sense amplifier are both placed in an inactive state.