Safety early warning system and method and vehicle

The invention relates to a safety early warning system and method and a vehicle, the system is applied to the vehicle, and the system comprises an early warning device arranged at the roof position of the vehicle; the control module is used for obtaining fault information and controlling the early warning device to be switched between a first state and a second state based on the fault information, when the early warning device is in the first state, the height of the early warning device is a first height, and when the early warning device is in the second state, the height of the early warning device is a second height. The height of the early warning device is a second height, and the first height is lower than the second height; and the control module is also used for controlling the early warning device to start so as to carry out early warning. The method has the effect of effectively warning the rear vehicle, and the driving safety can be improved.