Abstract: An apparatus for wakeup on LAN (WOL) has a programmable control apparatus, a computer system and an interface device. The interface device sends a power management event (PME) signal to the programmable control apparatus and the computer system, separately, after receiving a WOL package. When the computer system receives the PME signal during its normal state, such as a sleep mode or a running mode, the computer system in the sleep mode is restored to the running mode, and the computer system in the running mode keeps running. When the computer system receives the PME signal during an abnormal off state, such as a halt mode or its power being cut off abnormally, a reset module of the programmable control apparatus resets the computer system.