PURPOSE:To transmit surely and easily data from the ground to vehicles by discriminating and receiving automatically data corresponding to the running direction by the receiver on the vehicle when the vehicle comes within the receiving area of transmission data of a ground transmitter. CONSTITUTION:In a receiving unit on a vehicle, running direction discrimination part 14 detects the angle between the vehicle running direction and the earth magnetism direction and codes this angle, and road direction decision part 13 discriminates road direction data from received data, and data decision part 15 takes in received data only when the running direction and the road direction agree with each other. Here, A ground transmission unit is provided with a road direction storage part, and transmits vehicle data, where road direction data is added, to up and down vehicle lines alternately with waves. Then, when the vehicle comes within the receiving area of transmission data of the ground transmitter, data corresponding to the running direction is automatically discriminated and received by receiver 5 on the vehicle. As a result, data can be transmitted surely and easily from the ground to vehicles.