The switch circuit includes a MOS transistor one end of which is coupled to a power supply line and to a control terminal of which voltage is input, a switch coupled between the power supply line and one end of the MOS transistor or one end of which is coupled to the other end of the MOS transistor, a MOS transistor coupled between an output terminal and ground potential, and a series-connected switch and constant current source coupled to a connection point between an opposite-side end of the whole series-connected MOS transistor and switch to the power supply line and the control terminal of the MOS transistor and performing adjustment to prevent current from flowing from the MOS transistor to ground potential after the switch turns on until the MOS transistor turns on.