Aiming at the data transmission rate of traditional satellite-borne data transmission systems that cannot meet the needs of current payload data development, a satellite-borne high-speed data transmission system based on the 64B/66B protocol is proposed to improve the data transmission efficiency of the satellite-borne data transmission system, reduce the complexity of the system, and improve the system Reliability. In the Virtex-7 series FPGA, a high-speed serial transceiver (Gigabit Transceiver with Low Power) based on the 64B/66B protocol can provide a maximum data transmission rate of 11.3Gbps. This system provides 8 external data transmission channels with a transmission rate of 3.125Gbps and 4 internal data transmission channels with a transmission rate of 6.25Gbps. Through serious simulation of the system and hardware debugging and testing, the results show that the maximum data throughput rate of the system design is 80Gbps, which effectively improves the transmission rate of the system compared with the traditional satellite-borne digital transmission system.