Train communication system based on two CAN (controller area network) buses

A train communication system based on two CAN (controller area network) buses comprises a first CAN train bus and a second CAN train bus which penetrate through the whole train, wherein a microprocessor control subsystem on each train is divided into two groups which are respectively accessed into the first CAN train bus and the second CAN train bus, two ends of the first CAN train bus and the second CAN train bus are respectively connected with a first main processor and a second main processor in the driver rooms at two ends of the train, and door controllers at two sides of the train are respectively arranged in a secondary CAN bus network and connected with the first CAN train bus and the second CAN train bus by door gateways. A certain redundancy exists between the CAN buses of the communication system, the door controller are arranged in the secondary CAN bus network so as to ensure the normal communication of the door controllers, the two ends of the CAN bus network are communicated with the CAN train bus by the door gateways which are mutually redundant, each train is provided with two main processors which are mutually redundant, and the redundancy design can ensure the safety operation of the communication system.