A switch control system of HomePlug and method thereof are disclosed. At least a switch and a central server are connected to form a home network. By a switch identification number composed of a Medium Access Control Address (MAC address) of the switch and a server identification (ID), the central server identifies the status of each switch. By a power line, the central server connects with the switch for data transmission and switching the status of the switch. By the server ID, the switch is not affected by interference from other controller.