A control apparatus that controls a plurality of vehicles performing platoon travelling is provided. Each of the vehicles is provided with an inter-vehicle communication apparatus that performs an inter-vehicle communication with an other vehicle included in a column of the platoon travelling. At least some of the vehicles is provided with an external communication apparatus that performs an external communication based on own identification information given by a telecommunication company. The control apparatus is configured to control respective vehicles such that the number of vehicles capable of simultaneously performing the external communication is less than the number of vehicles included in the column.