WARNING DEVICE

The warning device includes a processor configured to set a warning target region on a rear-lateral side of a vehicle, and notify an occupant of the vehicle of a warning when a moving object located in the warning target region is expected to come into contact with a door of the vehicle. The processor is configured to set a predetermined area in a vehicle coordinate system based on the vehicle to the warning target region, and correct the predetermined area when the vehicle is obliquely stopped with respect to a white line of a road.