There is provided a semiconductor storage device in which memory cells can easily be set at a proper potential in standby mode, along with a reduction in the area of circuitry for controlling the potential of source lines of memory cells. A semiconductor storage device includes static-type memory cells and a control circuit. The control circuit includes a first switching transistor provided between a source line being coupled to a source electrode of driving transistors and a first voltage, a second switching transistor provided in parallel with the first switching transistor, and a source line potential control circuit which makes the first and second switching transistors conductive to couple the source line to the first voltage, when the memory cells are operating, and sets the first switching transistor non-conductive and sets a gate electrode of the second switching transistor coupled to the source line in standby mode.