To prevent collision with a preceding vehicle by stable behavior, based on a deterministic prediction result relating to behavior of the preceding vehicle.

It is predicted whether a preceding vehicle which is cruising on a right lane or a left lane relating to its own vehicle cruising lane will change its lane into the own vehicle cruising lane by a lane change prediction unit 52, based on: a blink state of a blinker of the preceding vehicle which is determined by a direction indication state determining unit 42; a position of the lane in which the preceding vehicle is cruising, and which is determined by a preceding vehicle lane determining unit 44; preceding vehicle information calculated by a preceding vehicle calculating unit 46; lane disappearance information acquired by a lane disappearance information acquiring unit 48; and obstruction information acquired by obstruction information acquiring unit 50. Then driving support is performed for a driver when the preceding vehicle is predicted as changing its lane into the own vehicle cruising lane.