Aiming at the problems of a large number of field sensors in the nuclear industry,long transmission distance,high requirements for real-time and stability,lack of centralized management means and inability to access the network,this paper designs and implements a centralized management system from serial port to can bus,which encapsulates the nuclear radiation data into frames and then transfers them to Ethernet for network transmission.With STM32F103 processor as the core,the system receives different radiation data into the three-stage FIFO mailbox,reads the data in FIFO through polling and encapsulates,puts the encapsulated data frame into the ring buffer,and finally transmits to the upper computer through the network port of the system that transits LwIP lightweight protocol stack.After testing the operation of three device nodes on CAN bus,the results show that the system is stable without error code and meets the design requirements.