A switching circuit includes first and second MOS transistors of the same conductive type. The second MOS transistor has a drain connected to a first terminal, a source connected to a load connecting terminal, a gate connected to a gate of the first MOS transistor, and a back gate connected to a source of the first MOS transistor. The switching circuit includes a circuit that controls a current flowing between the source of the first MOS transistor and a resistor connecting terminal so that the potential of the source of the first MOS transistor and the potential of the source of the second MOS transistor are equal. This switching circuit further includes a circuit that outputs a control signal to the gate of the first MOS transistor and the gate of the second MOS transistor and controls the operations of the first MOS transistor and the second MOS transistor.