A voltage regulator stably operates even when an operating current of a differential amplifier circuit is increased according to an output current. In the voltage regulator, a current mirror circuit for detecting the output current and increasing the operating current of the differential amplifier circuit is provided with a function of providing a delay according to an operation state of the voltage regulator. A simultaneous action of a main feedback system and a feedback system for the output current is eliminated, whereby an internal operating point can be prevented from fluctuating and therefore stability of the operation is improved.