Driving assistance apparatus

A driving assistance apparatus includes an on-board sensor, and a processor. The processor sets the lateral distance between a first long side and the own vehicle to a first predetermined value, and sets the lateral distance between a second long side and the own vehicle to a second predetermined value, when the own vehicle is traveling in the central part of a first lane in the width direction of the first lane, and sets the lateral distance between the first long side and the own vehicle to the first predetermined value, and sets the lateral distance between the second long side and the own vehicle to a value smaller than the second predetermined value, when the own vehicle is displaced toward a second lane adjacent to the first lane from the central part of the first lane in the width direction of the first lane.