The invention discloses a smoke warning system of a heavy truck, and belongs to the field of an automobile manufacturing technology. The system comprises a vehicle terminal wirelessly communicated with a background management system, wherein the vehicle terminal is connected with an information collector through a warner connected on a CAN (Controller Area Network) bus, and a signal input end of the information collector is connected with a signal output end of a smoke detector; when the smoke concentration in a compartment reaches a preset limit value, the smoke detector is used for outputting a smoke signal to the information collector, and the information collector is used for transmitting the smoke signal transmitted to the warner and the vehicle terminal; the warner is used for warning in accordance with the smoke signal, meanwhile, the vehicle terminal is used for transmitting the smoke signal to the background management system and displaying the smoke warning information and the control warning on the background management system. According to the smoke warning system provided by the invention, the problem that the heavy truck is on fire once the smoke in the compartment is omitted in the transportation process can be solved.