A traffic control system for allowing vehicles to travel unattended while maintaining their inter-vehicular distances without interfering with each other includes an onboard control apparatus mounted on the vehicles; and a traffic control apparatus which divides tracks for multiple vehicles into a plurality of sections and performs a blocking control to assign non-overlapping travelable sections to the multiple vehicles as a permitted travel section. The onboard control apparatus sets a travel permission request starting distance that is longer than a stoppable distance on the basis of the current speed of the vehicle and repeatedly transmits a travel permission request and current position information to the traffic control apparatus until the next travel permission is obtained when the remaining length of the permitted travel section has become shorter than the travel permission request starting distance in the advancing direction of the vehicle.