In view of the problems in transmission capacity of illumination guidance system, this paper presents a high speed of 2.5 Gbit/s optical system based on gigabit transceiver. The system takes gigabit transceiver as the core device. It is used to achieve a series of processing with multiple data types and multiple interface in optical fiber transmission and Field Programmable Gate Array (FPGA). It ultimately achieves the high-speed optical fiber transmission of serial data. The results show that the system can increase the processing rate of the data from guidance array to ground console. It also reduces the number of equipment in illumination guidance system, which breaks through the limit of transmission distance between guidance array and ground console.