A method and apparatus for providing additional information to a visible light communication terminal through visible light communication by an information display device having a back light unit is provided. The method includes, when the visible light communication terminal is located in one area corresponding to at least one additional information providing area that is disposed within a screen of the information display device, receiving time slot information allocated to the one area through the visible light communication, when the visible light communication terminal is located in remaining areas of the at least one area corresponding to the at least one object, except for the one area, receiving additional information on all objects from the remaining areas through the visible light communication, and acquiring additional information on the object corresponding to the one area from among the additional information on all the objects by using the allocated time slot information.