A hybrid-mode boost power factor corrector includes an inductor, a switch unit, a diode unit, a current-detecting unit, and a control unit. The inductor is coupled to a DC input power source. The switch unit is coupled to the inductor and a ground. The diode unit is coupled to the inductor and the switch unit. The current-detecting unit receives an inductor current flowing through the inductor and provides a current detection signal corresponding to the inductor current. The control unit is coupled to the current-detecting unit to receive the current detection signal. When the hybrid-mode boost power factor corrector is operated in a light-load condition, the control unit samples a peak value of the current detection signal; when the hybrid-mode boost power factor corrector is operated in a heavy-load condition, the control unit samples an average value of the current detection signal.