In a charging communication system in which a charging control device performs communication between an electric vehicle and a charging equipment, the electric vehicle is equipped with a first communication device and a second communication device both configured to communicate with the charging equipment by using the same signal line in the charging cable; and a signal line connection device configured to switch connection/disconnection between the second communication device and the signal line. The charging control device, which controls a battery on the electric vehicle, calculates an amount of change in a signal line voltage between before and after the signal line connection device connects the second communication device to the signal line, and the charging control device causes, when the amount of change does not fall within a predetermined allowable range, the signal line connection device to disconnect the second communication device from the signal line.