A semiconductor storage device capable of performing low-voltage operation, reducing standby current, and decreasing memory size is provided. The semiconductor storage device is a semiconductor device including first to fourth transistors and a capacitor. The first transistor has a function of supplying a first signal to the capacitor. The capacitor has a function of accumulating electric charge based on the first signal. The second transistor has a function of supplying the electric charge based on the first signal to a gate of the third transistor. The third transistor has a function of outputting a first potential to a wiring and a function of supplying the first potential to a gate of the fourth transistor. The fourth transistor has a function of supplying a second potential to the capacitor through the second transistor.