In a vehicle drive support device 10a including an optical beacon communicator 11 that acquires exterior information on roads from an optical beacon communicator 100 on the roadside outside a subject vehicle, a navigation system 12 that acquires interior information on roads inside the subject vehicle and a vehicle drive support processing unit 24 that performs vehicle drive support of the subject vehicle using the exterior information acquired by the optical beacon communicator 11, the vehicle drive support processing unit 24 changes use aspects of the exterior information for the vehicle drive support in accordance with the interior information acquired by the navigation system 12. Accordingly, it becomes possible to perform the vehicle drive support by more efficiently using the information from outside of the subject vehicle.