Abstract: A CRC (cyclic redundancy check) verification method based on redundant coding system is presented, the application of this method to the rail traffic signal control system will solve communication problems between the redundant coding system and other types of redundant coding or the non-redundant coding system. By integrating the redundancy check information into the CRC computing process, the redundant coding CRC obtained in fault-free situation is exactly the same as the standard CRC, and could ensure the normal communication function. While in case of system failure, the error information can be fed into the redundant coding CRC, the external redundancy / non-redundant system will verify the fault information, thus improve the system security and the fault detection rate.