A train control system includes an on-board device 3 mounted on a train 2; a vehicle radio set 4; wayside radio sets 5 that are disposed on a ground; and ground devices 6 disposed in every control sections defined on the track. In each control section, the ground device 6 is connected to the wayside radio sets 5 in the control section. When one ground device 6 fails to transmit information to and receive information from another ground device 6, the one ground device 6 determines that said another ground device 6 has been failed, and then, the one ground device 6 calculates a possible travel distance to a control section of the failed ground device 6 to prevent the train 2 from entering the control section of the failed ground device 6, and then, the one ground device 6 transmits the possible travel distance to the on-board device 3.