The invention discloses an airborne 1394b bus controller node backup system, and belongs to the technical field of airborne bus CC node fault reconstruction. Each bus is provided with a main CC node,a backup CC node, multiple reconstructive RN nodes and a conventional RN node; the main CC node sends an STOF packet through a channel 31, and the backup CC node sends an STOF packet through a channel32; the backup CC node is used as the conventional RN node on the condition that the main CC node is used normally; on the condition that the main CC node generates a fault, the backup CC node additionally achieves a function of sending the STOF packet on the basis of an original function of sending asynchronous flow packets; the reconstructive RN nodes monitor the STOF packets of the channel 31and the channel 32 simultaneously and send the asynchronous flow packets in an offset mode according to the monitoring conditions of the STOF packets respectively; and the conventional RN node only monitors the STOF packet of the channel 31, and if the conventional RN node cannot detect the STOF packet of the channel 31, the conventional RN node keeps silent. According to the airborne 1394b bus controller node backup system, the bus transmission reliability can be effectively improved, and the system needs a small logic change amount and can be downwards compatible with a traditional airborne1394b bus protocol.