Provided is a charging device assembly for an electric vehicle. The assembly includes a cable connecting the electric vehicle to a power supply unit, a charge control device coupled with the cable, a main bracket, to which the charge control device is attached to be detachable, and an ad-on communication device couplable with the main bracket. Herein, the charge control device includes an ad-on communication unit for wireless short-distance communication. The ad-on communication device includes a charge control device communication unit for wireless short-distance communication with the charge control device and a terminal communication unit for wireless communication with a terminal displaying one of charging operation and state of the electric vehicle.