A computer and a waking method thereof are provided. The computer includes a switch circuit, a chipset, a peripheral component interconnect express (PCIE) device, and an embedded controller. The chipset includes a first wake-up pin and a power button pin, wherein the first wake-up pin is coupled to a terminal of the switch circuit. The PCIE device includes a second wake-up pin, and the embedded controller includes a general purpose input pin and a general purpose output pin. The general purpose input pin and the second wake-up pin are coupled to another terminal of the switch circuit. The general purpose output pin is coupled to the power button pin.