An automatic vehicle positioning management system includes an on-vehicle apparatus and a portable device. The on-vehicle apparatus, installed on a vehicle, acquires a first location of the vehicle through wireless positioning. The first location is sent to the portable device which acquires a second location of the vehicle through GPS. When multiple vehicles form a fleet, each vehicle respectively sends its first and second locations to a server through its portable device. The second location of each vehicle is corrected by operations of point error analysis, image overlay and point error correction, so that the fleet can be managed more precisely.