A power control system includes a rectifier circuit, a buck circuit, a voltage divider circuit, a control circuit, and a switch circuit. A first terminal of the rectifier circuit is connected to an alternating current (AC) power supply. A second terminal of the rectifier circuit is connected to a first terminal of the buck circuit and a first terminal of the voltage divider circuit. A first terminal of the control circuit is connected to a second terminal of the buck circuit. A second terminal of the control circuit is connected to a second terminal of the voltage divider circuit. A third terminal of the control circuit is connected to the switch circuit. The switch circuit is connected to the AC power supply and an electronic device.