A method for operating an illumination system that includes at least one illumination device, a server configured to perform wireless communication with the illumination device, and a terminal configured to perform optical communication with the illumination device. The method includes sending information regarding an operation mode of the illumination device from the terminal to the server, sending a control signal from the server to the illumination device based on the information regarding an operation mode, performing visible light communication based on identification information of the illumination device when the illumination device receives the control signal, detecting the identification information of the illumination device through the terminal based on the visible light communication, matching the detected identification information with location information of the illumination device, and sending the identification information and the location information of the illumination device that are matched each other to the server.