To provide a regulator circuit capable of preventing oscillation of output voltage when an overcurrent regulating function is activated voltage across resistor 31 is lower than the voltage of voltage source VR2, output of hysteresis comparator 51 is low-level, n-type MOS transistor 63 is turned off, and capacitor 62 is charged to the voltage level of power supply line Vcc under the normal condition. On the other hand, under an overcurrent condition, hysteresis comparator 51 becomes high-level, n-type MOS transistor 63 is turned on, and the charge in capacitor 62 is discharged. Because differential amplifier circuit 41 selects the signal with a lower voltage out of 2 positive side input signals, negative feedback control is applied to the output voltage in reference to voltage source VR1 under the normal condition, and voltage source 64 under the overcurrent condition. In addition, because the voltage at positive input terminal +2 rises at a fixed rate when moving from the overcurrent condition to the normal condition, sudden changes in the output voltage can be restrained.