A power switch circuit includes a control circuit, and first and second detecting circuits. The control circuit includes first and second field effect transistors (FETs) and first and second sensing resistors. The first detecting circuit includes two input terminals connected to the first and second ends of the first sensing resistor and an output terminal connected to the first FET. The first detecting circuit controls the first FET to be turned on or turned off according to the voltages of the first and second ends of the first sensing resistor. The second detecting circuit includes two input terminals connected to the first and second ends of the second sensing resistor and an output terminal connected to the second FET. The second detecting circuit controls the second FET to be turned on or turned off according to the voltages of the first and second ends of the second sensing resistor.