A DC-DC converter control circuit, to control a DC-DC converter having an inductor and two switches, including a first feedback circuit; a second feedback circuit; a synthesis circuit to add a first feedback voltage indicating a DC component of an inductor current based on an output current of the DC-DC converter and a second feedback voltage indicating an AC component thereof to generate a third feedback voltage; a comparator to compare the third feedback voltage with a reference voltage to output a comparison result; and an on-time adjusting circuit to adjust on/off time of the switches based on the comparison result for outputting a control signal depending on the adjusting result. The second feedback voltage is generated based on a difference between input and output voltages of the DC-DC converter when the control signal is low and based on the output voltage when the control signal is high.