A regulator circuit is provided which has a reference voltage outputting unit, a first operational amplifier, a voltage-dividing unit, and a second operational amplifier. The reference voltage outputting unit is connected to a power source voltage, has a rectifying element, and outputs a first reference voltage. The first reference voltage is input to the first operational amplifier, and the first operational amplifier outputs a second reference voltage equal to the first reference voltage. The second reference voltage is input to the voltage-dividing unit, and the voltage-dividing unit outputs a third reference voltage having a voltage lower than the second reference voltage. The third reference voltage is input to the second operational amplifier, and the second operational amplifier outputs an output voltage equal to the third reference voltage.