A platooning control system includes a platoon controller that generates environmental maps used for platooning of vehicles, and a travel controller that controls travel of a following vehicle following a leading vehicle. The platoon controller generates the environmental maps each representing the position of an object around the vehicles, and delivers the maps to the following vehicle. The travel controller transmits object information indicating the position of an object detected from environmental data outputted by an environmental sensor mounted on the following vehicle to the platoon controller, executes update so that the position of the object represented in the latest environmental map is changed to the position of the object at the time when the following vehicle reaches the position of the leading vehicle represented in the latest environmental map, and controls travel of the following.