DRIVING SUPPORT DEVICE

The driving support device includes a control unit that acquires target information indicating a target on a road intersecting the intersection from the roadside device, determines a possibility of collision between the target and the vehicle at the intersection based on the target information and the own vehicle information indicating the state of the vehicle, determines to perform driving assistance to the driver of the vehicle based on the result of the determination, acquires vehicle operation information indicating a driving operation by the driver with respect to the driving assistance, and diagnoses a driving tendency of the driver based on the vehicle operation information.