A data transmission system with optical fiber interface to ethernet interface is designed in order to meet the needs of high-speed and reliable data transmission such as synthetic aperture radar real-time imaging and data playback, and to solve the problems that traditional data transmission systems are not suitable for field tests due to high interface requirements, large volume and power consumption, and inflexible network configuration. This paper mainly introduces the realization method of data transmission, and puts forward an optimization strategy of three-stage ping-pong and instruction parallel to ensure the correct data and improve the transmission speed. The network configuration can be flexibly modified by means of embedded Linux system. Compared with traditional systems, the system has obvious advantages in volume, power consumption and flexibility. Experimental results show that the data transmission speed can reach 770 Mb/s.