In a system and method for testing a wake-up on LAN (WOL) function of a computer, the computer connects to a server through a local area network (LAN). The system constructs a network connection between the server and the computer according to an Internet protocol (IP) address, a media access control (MAC) address and a name of the computer, and enables the computer in a wake-up mode when the server connects to the computer through the LAN. A wake-up command is generated for waking up a WOL function of the computer, the computer performs a WOL function test process according to the wake-up command. The sever detects a current status of the computer from a data packet when the data packet is received from the computer, and records the current status as a test result of the WOL function of the computer.