We have developed digital ATC for authorized Shinkansen project and carried out its field test. This paper gives an outline of this system and reports on the results of the field test. In Digital ATC system, ground equipment detects trains using track circuit and transmits the digital coded data through the track circuit. Wayside equipment transmits the ID of the track circuit and the number of the sections to a preceding train. The on-board equipment generates one stage braking profile using the on-board database and the data received from the track circuit. Be fitting the authorized Shinkansen, it can reduce the number of power amplifiers of the wayside equipment. It is adaptable to non-insulated track circuits. So, the initial and maintenance costs will be saved. We have carried out the field tests on Kagoshima Line in JR Kyushu. Using the prototype of the ground equipment and the on-board equipment, we verified that the Digital ATC can function as originally designed.