Disclosed is a regulator including: a differential amplifier having a differential input stage receiving a reference voltage and an output terminal voltage, a push-pull type output portion of a current mirror configuration, a drive transistor having a control terminal connected to an output portion of the differential amplifier, first and second transistors cascode-connected between a control terminal of the drive transistor and a power supply, and third and fourth transistors cascode-connected between the control terminal of the drive transistor and ground. Control terminals of the first and the third transistors are respectively connected to control terminals of the push-pull transistors, control terminals of the second and fourth transistors are respectively connected to a first and a second control signal. A voltage of the control terminal of the drive transistor is controlled, based on the first and the second control signals, by output of the differential amplifier and the first transistor, or by output of the differential amplifier and the third transistor.