An on-board device capable of receiving train control signals from ground-side equipment of train control systems of different types or the like to control the speed of a train and the like appropriately, is provided. An on-board device 10 mounted on a train 1 includes ATC/TD antennas 11a, 11b that receive an ATC signal including train control information from loop coils installed along a route of the train 1, a vehicle radio set 12 that receives a CBTC signal including train control information from wayside radio sets installed along the route, an ATC control unit 141 that controls the train 1 based on the train control information in the ATC signal, a CBTC control unit 142 that controls the train 1 based on the train control information in the CBTC signal, and a selection unit 143 that selects the ATC control unit 141 or the CBTC control unit 142.