The invention discloses a system and a method for train tail communication of a 10,000-ton combined train. The 10,000-ton combined train comprises a leading locomotive and a plurality of led locomotives. The system comprises a first radio station, a second radio station, a third radio station and a control device, wherein a train tail query operation is executed through the first radio station which is provided with a fixed query frequency; the second radio station is used for providing pilot signals; communication between the leading locomotive and the plurality of led locomotives and among the plurality of led locomotives is carried out through the third radio station which is provided with a plurality of different preset communication frequencies; and the control device is connected with the first radio station, the second radio station and the third radio station, used for receiving a serial number of the leading locomotive, determining the communication frequency of the leading locomotive according to the locomotive serial number of the number of the preset communication frequencies, and adjusting the communication frequency of the third radio station to the determined communication frequency so as to carry out communication. The preset communication frequency and the query frequency are not overlapped, and a problem that communication and train tail query are mutually interfered is solved.