This vehicle control system is provided with: a first device for generating trajectory data showing a future trajectory of a host vehicle and outputting the generated trajectory data; a second device for controlling at least one of acceleration/deceleration and steering of the host vehicle, on the basis of the trajectory data generated by the first device; and a third device that is at least separate from the first device, and that is for receiving the trajectory data generated by the first device and writing the received trajectory data on a storage unit of the host device, wherein when an abnormality occurs in the trajectory data outputted by the first device, the second device controls at least one of acceleration/deceleration and steering of the host vehicle, on the basis of the trajectory data that has been received and written on the storage unit by the third device before the occurrence of the abnormality.