A switching regulator has an error amplifier supplying an error current, a phase compensation portion generating an error voltage, a clamper clamping the error voltage, a PFM detector supplying a comparison result signal of a first level or a comparison result signal of a second level based on the error current, an oscillator supplying a clock signal in response to the comparison result signal at the second level and fixing the clock signal in response to the comparison result signal at the first level, and a PWM converter turning on/off a switching element with a desired pulse width based on the error voltage and the output from the oscillator.