A power saving apparatus and power saving method thereof are disclosed. The apparatus includes a power controller and a power outlet, wherein the power controller has a first signal transmission interface, said first signal transmission signal interface is used to detect the operation mode of a host machine by a second signal transmission interface of said host machine, and outputs a controlling signal according to the operation mode of said host machine. The power socket communicates with the power controller and switches the power-on or off according to the control signal. When the host machine is operated in non-working mode, the power socket will turn off the power supplied to the peripheral electrical devices of the host machines, so as to save the power consumption of the peripheral electrical devices of the host machines.