In order to meet the requirements of Ethernet, CAN head office and multi-channel serial port communication, a multi-channel serial port and Ethernet communication system based on DSP + FPGA is designed. Introduce the composition and working principle of DSP + FPGA-based multi-channel serial port and Ethernet communication system, and explain the structure of DSP circuit, FPGA circuit, and power circuit respectively, and explain the functions of system software. The application results show that the communication system has the advantages of stable operation and reliable performance, and can meet the needs of project development.