Provided are a vehicle control system (1) and a vehicle control device (7), wherein control of a support device (6) for supporting driving of the vehicle (2) can be switched between a normal driving mode in which the vehicle (2) is in motion while a power source (8) for moving the vehicle (2) is operated, and a coasting mode in which the vehicle (2) is in motion while the operation of the power source (8) is stopped. Accordingly, in the vehicle control system (1) and the vehicle control device (7), the control of the support device (6) is switched between the normal driving mode and the coasting mode, and thus, coasting of the vehicle (2) can be appropriately performed.