A vehicle rear warning system includes: a driving information detection portion that collects information measured from a radar and a camera sensor in a reverse mode of a vehicle; and a controller that separates a danger zone and a safe zone with reference to a fixed obstacle at a rear of the vehicle by performing fusion of the information measured from the radar and the camera in the reverse mode of the vehicle, and generates a collision event and controls warning and braking when a moving object approaching from the danger zone is detected, while limiting the warning and braking for a moving object existing in the safe zone.